University  of  California— College  of  Agriculture, 

AGRICULTURAL  EXPERIMENT  STATION, 

E.   W.    HILGARD,    Director. 


NATURE,  VALUE,  AND  UTILIZATION 
OF  ALKALI  LANDS. 


Alkali  Spots  Before  Reclamation.    Tulare  Experiment  Substation. 

BY 

E.    W.     HILGARD. 


BULLETIN  No.  128. 

(March,  1900.) 


SACRAMENTO: 
a.  j.  johnston,    :    :    :    :    :    superintendent  state  printing. 

1900. 


TABLE  OF  CONTENTS. 


Page. 

Occurrence  and  Characteristics  of  Alkali  Soils 3 

How  Plants  are  Injured  by  Alkali 5 

Effects  of  Irrigation __ 5 

Determination  of  the  Distribution  of  the  Alkali  Salts _ 6 

Composition  of  Alkali  Salts;  summary  of  conclusions 13 

Utilization  and  Reclamation  of  Alkali  Lands .        14 

Counteracting  Evaporation;   Diluting  the  Alkali  Salts  ;  Chemical  Remedies; 

Stable  Manure  and  Other  Fertilizers _.  14-18 

Removing  the  Salts  from  the  Soil 19 

Will  it  Pay  to  Reclaim  Alkali  Lands 20 

Crops  Suitable  for  Alkali  Lands _ 22 

Amount  of  Salts  Compatible  with  Ordinary  Crops. 24 

Grasses  ;  Legumes ;  Weeds ;  Root  Crops ;  Textile  Plants ;   Grapevines ;  Citrus 

Trees;  Deciduous  Orchard  Trees ;  Timber  and  Shade  Trees 24-29 

Irrigation  with  Saline  Waters  30 

Limits  of  Saline  Contents _ -...._ . 31 

Reclaimable  and  Irreclaimable  Alkali  Lands  as  distinguished  by  their  Natural 

Vegetation ._ 35 

Tussock  Grass ;  Greasewood ;  Dwarf  Samphire ;   Bushy  Samphire ;   Saltwort ; 

Alkali-Heath;  Cressa _ 37-44 

Relative  Tolerance  of  the  Different  Species 44 

Total  Salt  Indicators;  Salsoda  Indicators;  Neutral  Salt  Indicators 46 

ILLUSTRATIONS. 

Alkali  Spots  before  Reclamation... Title-page. 

Diagrams  showing  Distribution  of  Alkali  Salts ..7,  8,  10,  11 

Wheat  on  Soil  crusted  with  White  Alkali... ._ 17 

Alkali  Lands  in  San  Joaquin  Valley 21 

Orange  Trees  irrigated  with  Artesian  Water 32 

Orange  Trees  irrigated  with  Alkali  Water  of  Elsinore  Lake 33 

Alkali  Grasses:  Tussock  Grass;  Greasewood;  Dwarf  Samphire;  Bushy  Samphire; 

Saltwort;  Alkali-Heath;  Cressa 37-44 


THE  NATURE,  VALUE,  AND  UTILIZATION  OF 
ALKALI  LANDS.* 


By  E.  W.  Hilgaed. 


[The  continuous  and  pressing  demand  for  information  on  alkali  lands  and  their 
utilization  having  exhausted  the  printed  matter  heretofore  published  by  this  Station 
on  the  subject,  it  seems  best  to  publish  a  brief  general  summary  of  the  results  of  our 
investigations,  made  during  the  past  twenty  years,  for  the  use  of  farmers  and  land 
owners  and  the  general  public.  Those  desiring  more  detailed  information  will  find  the 
record,  so  far  as  printed,  in  the  reports  of  the  Station  from  1879  to  1898.] 

Occurrence  and  Characteristics  of  Alkali  Soils. 

Alkali  lands  must  be  pointedly  distinguished  from  the  salty  lands  of 
sea  margins  or  marshes,  from  which  they  differ  in  both  their  origin  and 
essential  nature.  Marsh  lands  derive  their  salts  from  sea  water  that 
occasionally  overflows  them,  and  the  salts  which  impregnate  them  are 
essentially  "sea  salts";  that  is,  common  salt,  together  with  bittern, 
epsom  salt,  etc.  Very  little  of  what  would  be  useful  to  vegetation  or 
desirable  as  a  fertilizer  is  contained  in  the  salts  impregnating  such 
soils;  and  they  are  by  no  means  always  intrinsically  rich  in  plant 
food,  but  vary  greatly  in  this  respect. 

Alkali  lands  bear  no  definite  relation  to  the  sea;  they  are  mostly 
remote  from  it  or  from  any  former  sea  bed,  so  that  they  have  sometimes 
been  designated  as  "terrestrial  salt  lands."  Their  existence  is  usually 
definitely  traceable  to  climatic  conditions  alone.  They  are  the  natural 
result  of  a  light  rainfall,  insufficient  to  leach  out  of  the  land  the  salts 
that  always  form  in  it  by  the  progressive  weathering  of  the  rock 
powder  of  which  all  soils  largely  consist.  Where  the  rainfall  is 
abundant,  that  portion  of  the  salts  corresponding  to  "sea  salts"  is 
leached  out  into  the  bottom  water,  and  with  this  passes  through 
springs  and  rivulets  into  the  country  drainage,  to  be  finally  carried  to 
the  ocean.  Another  portion  of  the  salts  formed  by  weathering,  however, 
is  partially  or  wholly  retained  by  the  soil;  it  is  that  portion  chiefly 
useful  as  plant-food. 

It  follows  that  when,  in  consequence  of  insufficient  rainfall,  all  or 
most  of  the  salts  are  retained  in  the  soil,  they  will  contain  not  only 

*  Revision  of  a  paper  published  in  the  Yearbook  of  the  U.  S.  Department  of  Agricul- 
ture for  1895,  with  abstracts  from  reports  and  records  of  the  California  Experiment 
Station. 


—  4  — 

the  ingredients  of  sea  water,  but  also  those  useful  to  plants.  In  rainy 
climates  a  large  portion  even  of  the  latter  is  leached  out  and  carried 
away.  In  extremely  arid  climates  their  entire  mass  remains  in  the 
soils;  and,  being  largely  soluble  in  water,  evaporation  during  the  dry 
season  brings  them  to  the  surface,  where  they  may  accumulate  to  such 
an  extent  as  to  render  the  growth  of  ordinary  useful  vegetation  impos- 
sible; as  is  seen  in  "alkali  spots,"  and  sometimes  in  extensive  tracts  of 
"alkali  desert." 

In  looking  over  a  rainfall  map  of  the  globe  we  see  that  a  very  consider- 
able portion  of  the  earth's  surface  has  deficient  rainfall,  the  latter  term 
being  commonly  meant  to  imply  any  annual  average  less  than  20 
inches  (500  millimeters).  The  arid  region  thus  defined  includes,  in 
North  America,  most  of  the  country  lying  west  of  the  one  hundredth 
meridian  up  to  the  Cascade  Mountains,  and  northward  beyond  the 
line  of  the  United  States;  southward,  it  reaches  far  into  Mexico,  includ- 
ing especially  the  Mexican  plateau.  In  South  America  it  includes 
nearly  all  the  Pacific  Slope  (Peru  and  Chile)  south  to  Araucania;  and 
eastward  of  the  Andes,  the  greater  portion  of  the  plains  of  western 
Brazil  and  Argentina.  In  Europe  only  a  small  portion  of  the  Mediter- 
ranean border  is  included;  but  the  entire  African  coast  belt  opposite, 
with  the  Saharan  and  Libyan  deserts,  Egypt,  and  Arabia  are  included 
therein,  as  well  as  a  considerable  portion  of  South  Africa.  In  Asia, 
Asia  Minor,  Syria  (with  Palestine),  Mesopotamia,  Persia,  and  north- 
western India  up  to  the  Ganges,  and  northward,  the  great  plains  or 
steppes  of  central  Asia  eastward  to  Mongolia  and  western  China,  fall 
into  the  same  category;  as  does  also  a  large  portion  of  the  Australian 
continent. 

Over  these  vast  areas  alkali  lands  occur  to  a  greater  or  less  extent, 
the  exceptions  being  the  mountain  regions  and  adjacent  lands  on  the 
side  Exposed  to  prevailing  oceanic  winds.  It  will  therefore  be  seen  that 
the  problem  of  the  utilization  of  alkali  lands  for  agriculture  is  not  of 
local  interest  only,  but  is  of  world-wide  importance.  It  will  also  be 
noted  that  many  of  the  countries  referred  to  are  those  in  which  the 
most  ancient  civilizations  have  existed  in  the  past,  but  which  at 
present,  with  few  exceptions,  are  occupied  by  semicivilized  people 
only.  It  is  doubtless  from  this  cause  that  the  nature  of  alkali  lands 
has  until  now  been  so  little  understood  that  even  their  essential  dis- 
tinctness from  the  sea-border  lands  has  been  but  lately  recognized  in 
full.  Moreover,  the  great  intrinsic  fertility  of  these  lands  has  been 
very  little  appreciated,  their  repellent  aspect  causing  them  to  be  gen- 
erally considered  as  waste  lands. 

This  aspect  is  essentially  due  to  their  natural  vegetation  being  in 
most  cases  confined  to  plants  useless  to  man,  commonly  designated 
as   "  saline   vegetation,"   of  which   but   little   is   usually    relished   by 


—  5  — 

cattle.  Notable  exceptions  to  this  rule  occur  in  Australia  and  Africa, 
where  the  "  saltbushes "  of  the  former  and  the  "  karroo "  vegetation  of 
the  latter  form  valuable  pasture  grounds.  Apart  from  these,  however, 
the  efforts  to  find  for  these  lands  while  in  their  natural  condition,  cul- 
ture plants  generally  acceptable,  or  at  least  profitable,  outside  of  forage 
crops,  have  not  been  very  successful. 

How  Plants  Are  Injured  by  Alkali. 

When  we  examine  plants  that  have  been  injured  by  alkali,  we  will 
usually  find  that  the  damage  has  been  done  near  the  base  of  the  trunk, 
or  root  crown;  rarely  at  any  considerable  depth  in  the  soil  itself.  In  the 
case  of  green  herbaceous  stems,  the  bark  is  found  to  have  turned  to  a 
brownish  tinge  for  half  an  inch  or  more,  so  as  to  be  soft  and  easily 
peeled  off.  In  the  case  of  trees,  the  rough  bark  is  found  to  be  of  a  dark, 
almost  black,  tint,  and  the  green  layer  underneath  has,  as  in  the  case 
of  an  herbaceous  stem,  been  turned  brown  to  a  greater  or  less  extent. 
In  either  case  the  plant  has  been  practically  "girdled,"  the  effect  being 
aggravated  by  the  diseased  sap  poisoning,  more  or  less,  the  whole  stem 
and  roots.  The  plant  may  not  die,  but  it  will  be  quite  certain  to  become 
unprofitable  to  the  grower. 

It  is  mainly  in  the  case  of  land  very  heavily  charged  with  common 
salt,  as  in  the  marshes  bordering  the  sea  or  salt  lakes,  that  injury  arises 
from  the  direct  effects  of  the  salty  soil-water  upon  the  feeding  roots 
themselves.  In  a  few  cases  the  gradual  rise  of  salt  water  from  below, 
in  consequence  of  defective  drainage,  has  seriously  injured,  and  even 
destroyed,  old  orange  orchards. 

The  fact  that  in  cultivated  land  the  injury  is  usually  found  to  occur 
near  the  surface  of  the  soil,  concurrently  with  the  well-known  fact  that 
the  maximum  accumulation  of  salts  at  the  surface  is  always  found  near 
the  end  of  the  dry  season,  indicates  clearly  that  this  accumulation  is 
due  to  evaporation  at  the  surface.  The  latter  is  often  found  covered 
with  a  crust  consisting  of  earth  cemented  by  the  crystallized  salts,  and 
later  in  the  season  with  a  layer  of  whitish  dust  resulting  from  the 
drying-out  of  the  crust  first  formed.  It  is  this  dust  wrhich  becomes  so 
annoying  to  the  inhabitants  and  travelers  in  alkali  regions,  when  high 
winds  prevail,  irritating  the  eyes  and  nostrils  and  parching  the  lips. 

Effects  of  Irrigation. 

One  of  the  most  annoying  and  discouraging  features  of  the  cultiva- 
tion of  lands  in  alkali  regions  is  that,  although  in  their  natural 
condition  they  may  show  but  little  alkali  on  their  surface,  and  that 
mostly  in  limited  spots,  usually  somewhat  depressed  below  the  general 
surface,  these  spots  are  found  to  enlarge  rapidly  as  irrigation  is  prac- 
ticed; and  since  alkali  salts  are  the  symptoms  and  result  of  insufficient 


—  6  — 

rainfall,  irrigation  is  a  necessary  condition  of  agriculture  wherever 
they  prevail.  Under  irrigation,  neighboring  spots  will  oftentimes 
merge  together  into  one  large  one,  and  at  times  the  entire  area,  once 
highly  productive  and  perhaps  covered  with  valuable  plantations  of 
trees  or  vines,  will  become  incapable  of  supporting  useful  growth. 
This  annoying  phenomenon  is  popularly  known  as  "  the  rise  of  the 
alkali "  in  the  western  United  States,  but  is  equally  well  known  in 
India  and  other  irrigation  regions. 

The  process  by  which  the  salts  rise  to  the  surface  is  the  same  as  that 
by  which  oil  rises  in  a  wick.  The  soil  being  impregnated  with  a  solution 
of  the  alkali  salts,  and  acting  like  the  wick,  the  salts  naturally  remain 
behind  on  the  surface  as  the  water  evaporates,  the  process  only  stopping 
when  the  moisture  in  the  soil  is  exhausted.  We  thus  not  infrequently 
find  that  after  an  unusually  heavy  rainfall  there  follows  a  heavier  accu- 
mulation of  alkali  salts  at  the  surface,  while  a  light  shower  produces  no 
perceptible  permanent  effect.  We  are  thus  taught  that,  within  certain 
limits,  the  more  water  evaporates  during  the  season  the  heavier  will  be 
the  rise  of  the  alkali;  provided  that  the  water  is  not  so  abundant  as  to 
leach  the  salts  through  the  soil  and  subsoil  into  the  subdrainage. 

Worst  of  all,  however,  is  the  effect  of  irrigation  ditches  laid  in  sandy 
lands  (such  as  are  naturally  predominant  in  arid  regions),  without  proper 
provision  against  seepage.  The  ditch  water  then  gradually  fills  up  the 
entire  substrata  so  far  as  they  are  permeable,  and  the  water-table  rises 
from  below  until  it  reaches  nearly  to  the  ditch  level;  shallowing  the 
subsoil,  drowning  out  the  deep  roots  of  all  vegetation,  and  bringing  close 
to  the  surface  the  entire  mass  of  alkali  salts  previously  diffused  through 
many  feet  of  substrata.  If  this  condition  is  allowed  to  continue  for 
some  time,  alkali  salts  originally  "white"  will  by  a  chemical  change 
become  "black"  by  the  formation  of  carbonate  of  soda  from  the  glauber 
salt;  greatly  aggravating  the  injury  to  vegetation.  More  than  this,  if 
such  swamping  is  allowed  to  continue  for  a  number  of  years,  the  land 
may  be  permanently  injured;  so  that  even  after  the  alkali  is  removed, 
the  soil  remains  inert  and  unthrifty  for  years. 

Determination  of  the  Distribution  of  the  Alkali  Salts. 

In  order  to  gain  a  basis  for  the  possible  means  of  reclaiming  alkali 
lands,  it  is  evidently  necessary  to  determine  by  direct  observation  the 
manner  in  which  the  salts  are  distributed  in  the  soils  under  different 
conditions.  This  can  be  done  by  sampling  the  soil  at  short  intervals  of 
depth,  and  leaching  out  and  analyzing  each  sample  separately.  While 
this  involves  a  great  deal  of  work,  it  is  manifestly  the  only  conclusive 
method. 

A  series  of  such  investigations  has  been  first  carried  out  by  the  Cali- 
fornia Experiment  Station  during  the  years  1894  and  1895,  with  samples 


—  7  — 


taken  in  or  near  the  substations 
near  Tulare  and  Chino,  Cal., 
with  the  results  as  given  below. 
It  should  be  understood  that 
the  alkali  in  the  Tulare  region 
is  mostly  of  the  "black"  kind, 
that  is,  consisting  largely  of  car- 
bonate of  soda,  which  dissolves 
the  humus  of  the  soil  and  thus 
gives  rise  to  dark-colored  spots 
and  water-puddles.  The  soil  is 
a  rather  sandy,  gray  loam  (see 
Report  California  Experiment 
Station,  1889).  On  the  Chino 
tract,  on  the  contrary,  the  soil 
is  a  close-grained,  rather  heavy 
loam,  naturally  subirrigated; 
the  salts  are  likewise  mostly 
"  black,"  the  sodium  carbonate 
being  about  one  third  of  the 
whole. 

Fig.  1  represents  the  condition 
of  the  salts  in  an  "alkali  spot" 
as  found  at  the  end  of  the  dry 
season  at  the  Tulare  substa- 
tion. The  soil  was  sampled  to 
the  depth  of  2  feet,  at  intervals 
of  3  inches  each.  The  depths 
are  entered  in  the  vertical  line 
to  the  left;  the  percentages  of 
the  total  salts  and  of  each  of  the 
principal  ingredients  are  entered 
in  decimal  fractions  of  1  per 
cent  on  horizontal  lines  running 
to  the  right,  as  indicated  on  the 
top  line  of  the  plate.  Broken 
lines  connecting  the  data  in  each 
case  facilitate  the  understanding 
of  the  results.  It  is  thus  easy 
to  see  that  at  this  time  almost 
the  entire  mass  of  the  salts  was 
accumulated  within  the  first  six 
inches  from  the  surface,  while 
lower  down  the  soil  contained 
so  little  that  few  culture  plants 


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—  9  — 

Fig.  2  represents  similarly  the  state  of  things  in  a  natural  soil  along- 
side of  the  alkali  spot,  but  in  which  the  native  vegetation  of  brilliant 
flowers  develops  annually  without  any  hindrance  from  alkali.  Samples 
were  taken  from  this  spot  in  March,  near  the  end  of  the  wet,  and  in 
September,  near  the  end  of  the  dry,  season,  and  each  series  fully 
analyzed.  There  was  scarcely  a  noticeable  difference  in  the  results 
obtained.  It  is  seen  in  the  figure  that  down  to  the  depth  of  15  inches 
there  was  practically  no  alkali  found  (0.035%), and  it  was  within  these  15 
inches  of  soil  that  the  native  plants  mostly  had  their  roots  and  developed 
their  annual  growth.  But  from  that  level  downward  the  alkali  rapidly 
increased,  and  reached  a  maximum  (0.529%)  at  about  33  inches,  decreas- 
ing rapidly  thence  until,  at  the  end  of  the  fourth  foot  in  depth,  there  was 
no  more  alkali  than  within  the  first  foot  from  the  surface.  In  other 
words,  the  bulk  of  the  salts  had  accumulated  at  the  greatest  depth  to 
which  the  annual  rainfall  (7  inches)  ever  reaches,  forming  there  a  sheet 
of  tough,  intractable  clay  hardpan.  The  shallow-rooted  native  plants 
germinated  their  seeds  freely  on  the  alkali-free  surface,  their  roots  kept 
above  the  strongly  charged  subsoil,  and  through  them  and  the  stems 
and  foliage  all  the  soil  moisture  was  evaporated  by  the  time  the  plants 
died.  Thus  no  alkali  was  brought  up  from  below  by  evaporation.  The 
seeds  shed  would  remain  uninjured,  and  would  again  germinate  the 
coming  season. 

It  is  thus  that  the  luxuriant  vegetation  of  the  San  Joaquin  plains, 
dotted  with  occasional  alkali  spots,  is  maintained,  the  spots  them- 
selves being  almost  always  depressions  in  which  the  rain  water  may 
gather,  and  where,  in  consequence  of  the  increased  evaporation,  the 
noxious  salts  have  risen  to  the  surface  and  render  impossible  all  but 
the  most  resistant  saline  growth;  particularly  when,  in  consequence  of 
maceration  and  fermentation  in  the  soil,  the  formation  of  carbonate  of 
soda  (black  alkali)  has  caused  the  surface  to  sink  and  become  almost 
water-tight. 

After  several  years'  cultivation  with  irrigation  on  the  same  land  as 
in  the  last  figure,  a  crop  of  barley  4  feet  high  was  grown  on  the  land. 
Investigation  proved  that  here  the  condition  of  the  soil  was  intermediate 
between  the  two  preceding  figures.  The  irrigation  water  had  dissolved 
the  alkali  of  the  subsoil,  and  the  abundant  evaporation  had  brought  it 
nearer  the  surface;  but  the  shading  by  the  barley  crop  and  the  evapo- 
ration of  the  moisture  through  its  roots  and  leaves  had  prevented  the 
salts  from  reaching  the  surface  in  such  amounts  as  to  injure  the  crop, 
although  the  tendency  to  rise  was  clearly  shown. 

Ten  feet  from  this  spot  was  bare  alkali  ground  on  which  barley  had 
refused  to  grow.  Its  examination  proved  it  to  contain  a  somewhat 
larger  proportion  (one-fifth  more)  of  alkali  salts,  and  in  these  a  larger 
relative  proportion  of  carbonate  of  soda  (salsoda).  Thus  the  seed  was 
mostly  destroyed   before   germination,  and  of  the  few   seedlings   none 


—  10 


lived  beyond  the  fourth  leaf.  On  the  ground  represented  by  Fig.  1, 
previous  treatment  with  gypsum  had  so  far  diminished  the  salsoda 
that  the  grain  germinated  freely,  and  a  very  good  crop  of  barley  was 
harvested  there  without  irrigation.  The  same  season,  grain  crops  were 
almost  a  failure  on  alkali-free  land  in  the  same  region. 

In  connection  with  this  result  it  should   be  noted  as  a  general  fact 

Amounts  of  Ingredients  in  100  of  Soil. 
O         .  02        Q«        OS         Off         SO         /2  '¥         /6         /#        .20        .22 


Fig.  3.    Distribution  of  alkali  salts  in  sandy  land. 

that  alkali  lands  always  retain  a  certain  amount  of  moisture  perceptible 
to  the  hand  during  the  dry  season,  and  that  this  moisture  can  be 
utilized  by  crops;  so  that  at  times  when  crops  fail  on  nonalkaline  land, 
good  ones  are  obtained  where  a  slight  taint  of  alkali  exists  in  the  soil. 
Striking  examples  of  this  fact  occur  in  the  Spokane  country  within  the 
great  bend  of  the  Columbia  River,  in  the  State  of  Washington;  and  the 


—  11 


same  is  illustrated  by  the  luxuriant  growth  of  weeds  on  the  margin  of 
alkali  spots,  just  beyond  the  limit  of  corrosive  injury.  Actual  deter- 
mination showed  that  while  a  sample  of  alkali  soil  containing  .54  per 
cent  of  salts  absorbed  12.3  per  cent  of  moisture  from  moist  air,  the  same 
soil  when  leached  absorbed  only  2.5  per  cent — a  figure  corresponding  to 
that  of  sandy  upland  loams.  Investigation  at  the  Tulare  substation 
during  the  dry  season  of  1898  also  showed  the  presence  of  15  and  16  per 
cent  of  water,  respectively,  in  strong  u white"  and  " black"  alkali  soils, 
while  in  adjoining  light  alkali  soils  there  was  but  10  per  cent. 

In  very  sandy  lands,   and  particularly  when    the   alkali  is  "white" 
only,  the  tendency  to  accumulation  near  the  surface  is  much  less,  even 


under  irrigation. 


In  the  natural  condition  the  salts   are  in  such  cases 


Amounts  of  Alkali  Salts  in  100  or  Soil. 


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Fig.  4.    Distribution  of  alkali  salts  in  close-texiured  soil  of  the  ten-acre  tract,  near  Chino,  Cal. 

often  found  quite  evenly  distributed  through  soil  columns  of  four  feet, 
and  even  more.  This  is  an  additional  cause  of  the  lesser  injuriousness 
of  "white  alkali." 

Fig.  3  shows  the  distribution  of  the  salts  as  found  in  a  very  sandy 
area  on  the  Tulare  substation  grounds.  It  should  be  noted  that  here, 
while  the  general  figure  representing  the  distribution  is  very  similar  to 
that  showing  the  same  in  a  close  soil  (see  Fig.  4)  the  salts  reach  down 
to  over  6  feet,  and  are  at  their  maximum  18  inches  from,  instead  of  at 
the  surface. 

The  mode  of  distribution  of  alkali  salts  in  the  heavier,  close-grained 
soil  of  the  Chino  tract  is  illustrated  in  Fig.  4.  As  has  been  mentioned, 
this  land  is  permanently  moist,  from  a  water-table  ranging  from  5  to  7 


—  12  — 

feet  below  the  surface  in  ordinary  years.  There  is  therefore  no  oppor- 
tunity for  the  formation  of  "alkali  hardpan"  as  in  the  case  of  the 
Tulare  soil;  the  salts  always  remain  rather  near  the  surface,  viz,  within 
12  to  18  inches.  But  being  in  much  smaller  average  amounts  than  at 
Tulare  (an  average  of  about  5,300  pounds  per  acre),  quite  a  copious 
natural  vegetation  of  grasses,  sunflowers,  anc£" verba  mansa"  covered 
the  whole  surface,  save  in  a  few  low  spots. 

A  similar  mode  of  distribution  of  the  salts  is  found  in  the  more  clayey 
"black  adobe"  lands  of  the  Great  Valley  of  California.  The  scanty 
rains  cannot  penetrate  these  soils  to  any  great  depth,  so  that  evapora- 
tion will  soon  bring  the  salts  carried  by  them  back  to  within  a  short 
distance  of  the  surface.  Their  accumulation  there  is  frequently  indi- 
cated by  the  entire  absence  of  any  but  the  most  resistant  alkali  weeds, 
even  though  the  total  of  salts  in  the  land  may  not  be  very  great. 

While  the  phenomena  of  alkali  lands  as  outlined  above  undoubtedly 
represent  the  vastly  predominant  conditions  on  extensive  level  lands, 
yet  there  are  exceptions  due  to  surface  conformation,  and  to  the  local 
existence  of  sources  of  alkali  salts  outside  of  the  soil  itself.  Such  is  the 
case  where  salts  ooze  out  of  strata  cropping  out  on  hillsides,  as  is  the 
case  at  some  points  in  the  San  Joaquin  Valley  in  California,  and  in 
parts  of  Colorado,  Wyoming,  and  Montana.  In  such  cases  the  alkali 
salts  may  be  most  apparent  near  the  foot  of  the  hills,  and  in  light, 
well-drained  valley  lands  may  disappear  altogether  before  reaching  the 
valley-trough. 

On  the  other  hand,  it  not  infrequently  happens  that  in  sloping  val- 
leys or  basins,  where  the  central  (lowest)  portion  receives  the  salts 
leached  out  of  the  adjacent  hills  and  valley  slopes  in  consequence 
of  slow  subdrainage,  we  find  belts  of  greater  or  less  width  in  which  the 
alkali  impregnation  may  reach  to  the  depth  of  10  or  12  feet,  usually 
within  more  or  less  definite  layers  of  calcareous  hardpan,  likewise  the 
outcome  of  the  leaching  of  the  valley  slopes.  Such  areas,  however,  are 
usually  quite  limited,  and  are,  of  course,  scarcely  reclaimable  without 
excessive  expenditure,  the  more  as  they  are  often  underlaid  by  saline 
bottom  water.  In  these  cases  the  predominant  saline  ingredient  is 
usually  common  salt,  as  might  be  expected,  and  as  is  exemplified  on  a 
large  scale  in  the  Great  Salt  Lake  of  Utah,  and  in  the  ocean  itself. 

In  many  cases,  in  California  and  elsewhere,  the  over-irrigation  of 
bench  or  slope  lands  has  caused,  first  the  lower  slopes,  and  then  the 
bottom  lands  of  streams  and  rivers,  to  be  overrun  with  alkali  salts, 
although  before  irrigation  was  practiced  these  lands  were  exempt  from 
them.  In  some  portions  of  the  San  Joaquin  Valley  this  trouble  has 
become  most  serious,  fertile  lands  long  under  successful  cultivation 
being  rendered  useless  by  thousands  of  acres,  unless  an  expensive 
system  of  underdrainage  were  resorted  to.     Even  this  remedy  is  largely 


—  13  — 

inapplicable  in  the  absence  of  legislation  providing  for  right-of-way  for 
drainage  as  well  as  for  irrigation;  but  any  such  legislation  should,  at 
the  same  time,  provide  a  remedy  for  the  leakage  of  ditch-water,  which 
is  the  original  cause  of  the  injury. 

Composition  of  Alkali   Salts. 

Broadly  speaking,  it  may  be  said  that,  the  world  over,  alkali  salts 
consist  of  three  chief  ingredients,  namely,  common  salt,  glauber  salt 
(sulphate  of  soda),  and  salsoda  or  carbonate  of  soda.  The  latter 
causes  what  is  popularly  known  as  "  black  alkali,"  from  the  black 
spots  or  puddles  seen  on  the  surface  of  lands  tainted  with  it,  owing  to 
the  dissolution  of  the  soil  humus;  while  the  other  salts,  often  together 
with  epsom  salt,  constitute  "  white  alkali,"  which  is  known  to  be  very 
much  milder  in  its  effect  on  plants  than  the  black.  In  most  cases  all 
three  are  present,  and  all  may  be  considered  as  practically  valueless  or 
noxious  to  plant  growth.  With  them,  however,  there  are  almost  always 
associated,  in  varying  amounts,  sulphate  of  potash,  phosphate  of  soda, 
and  nitrate  of  soda,  representing  the  three  elements — potassium,  phos- 
phorus, and  nitrogen — upon  the  presence  of  which  in  the  soil,  in  avail- 
able form,  the  welfare  of  our  crops  so  essentially  depends,  and  which  we 
aim  to  supply  in  fertilizers.  The  potash  salt  is  usually  present  to  the 
extent  of  from  5  to  20  per  cent  of  the  total  salts;  phosphate,  from  a 
fraction  to  as  much  as  4  per  cent;  the  nitrate,  from  a  fraction  to  as 
much  as  20  per  cent.  In  black  alkali  the  nitrate  is  usually  low,  the 
phosphate  high;  in  the  white,  the  reverse  is  true. 

It  is  thus  clear  that  if  we  were  to  make  a  rule  of  reclaiming  alkali 
lands  by  leaching  out  the  salts  with  abundance  of  irrigation  water,  we 
would  get  rid  not  only  of  the  noxious  salts,  but  also  of  those  ingredients 
upon  which  productiveness  primarily  depends,  and  for  which  we  pay 
heavily  in  fertilizers.     This  is  evidently  to  be  avoided,  if  possible. 

Summing  up  the  conclusions  from  the  foregoing  observations  and 
considerations  we  find  that — 

(1)  The  amount  of  soluble  salts  in  alkali  soils  is  usually  limited; 
they  are  not  ordinarily  supplied  in  indefinite  quantities  from  the  bottom 
water  below.  These  salts  have  essentially  been  formed  by  weathering, 
in  the  soil  layer  itself. 

(2)  The  salts  ordinarily  move  up  and  down  within  the  upper  4  or  5 
feet  of  the  soil  and  subsoil,  following  the  movement  of  the  moisture; 
descending  in  the  rainy  season  to  the  limit  of  the  annual  moistening  as 
a  maximum,  and  then  reascending  or  not  according  as  surface  evapora- 
tion may  demand.  At  the  end  of  the  dry  season,  in  untilled  irrigated 
land,  practically  the  entire  mass  of  salts  may  be  within  6  or  8  inches 
of  the  surface. 


—  14  - 

(3)  The  injury  to  vegetation  is  caused  mainly,  sometimes  wholly, 
within  a  few  inches  of  the  surface,  by  the  corrosion  of  the  bark,  usually 
near  the  root  crown.  This  corrosion  is  strongest  when  carbonate  of  soda 
(salsoda)  forms  a  large  proportion  of  the  salts;  the  soda  then  also  dis- 
solves the  vegetable  mold  and  causes  blackish  spots  in  the  soil,  popu- 
larly known  as  black  alkali. 

(4)  The  injury  caused  by  carbonate  of  soda  is  aggravated  by  its 
action  in  puddling  the  soil  so  as  to  cause  it  to  lose  its  flaky  condition, 
rendering  it  almost  or  quite  untillable.  It  also  tends  to  form  in  the 
depths  of  the  soil  layer  a  tough  hardpan,  impervious  to  water,  which 
yields  to  neither  plow,  pick,  nor  crowbar,  and  renders  drainage  and 
leaching  impossible.  Its  presence  is  easily  ascertained  by  means  of  a 
pointed  steel  sounding  rod. 

(5)  While  alkali  lands  share  with  other  soils  of  the  arid  region  the 
advantage  of  unusually  high  percentages  of  plant-food  in  the  insoluble 
form,*  they  also  contain,  alongside  of  the  noxious  salts,  considerable 
amounts  of  water-soluble  plant-food.  When,  therefore,  the  action  of  the 
noxious  salts  is  done  away  with,  they  should  be  profusely  and  lastingly 
productive;  particularly  as  they  are  always  naturally  somewhat  moist 
in  consequence  of  the  attraction  of  moisture  by  the  salts,  and  are  there- 
fore less  liable  to  injury  from  drought  than  the  same  soils  when  free 
from  alkali. 

Utilization  and  Reclamation  op1  Alkali  Lands. 

The  most  obvious  mode  of  utilizing  alkali  lands  is  to  occupy  them 
with  useful  plants  that  are  not  affected  by  the  noxious  salts.  Unfortu- 
nately, as  has  already  been  stated,  but  few  such  crops  of  general  utility, 
especially  for  the  commercial  and  labor  conditions  of  this  country,  have 
as  yet  been  found.  Practically  the  most  important  problem  is  to  render 
these  lands  available  for  our  ordinary  cultures,  by  methods  financially 
possible. 

Counteracting  Evaporation. — Since  evaporation  of  the  soil  moisture 
at  the  surface  is  what  brings  the  alkali  salts  to  the  level  where  the 
main  injury  to  plants  occurs,  it  is  obvious  that  evaporation  should  be 
prevented  as  much  as  possible.  This  is  the  more  important,  as  the 
saving  of  soil  moisture,  and  therefore  of  irrigation  water,  is  attainable 
by  the  same  means. 

Three  methods  for  this  purpose  are  usually  practiced  by  farmers  and 
gardeners,  viz,  shading,  mulching,  and  the  maintenance  of  loose  tilth 
in  the  surface  soil  to  such  depth  as  may  be  required  by  the  climatic 
conditions. 


*See  Bulletin  No.  3  of  the  U.  S.  Weather  Bureau,  1892;  Report  California  Station, 
1894-5. 


—  15  — 

As  to  mulching,  it  is  already  well  recognized  in  the  alkali  regions  of 
California  as  an  effective  remedy  in  light  cases.  Fruit  trees  are  fre- 
quently thus  protected,  particularly  while  young,  after  which  their 
shade  alone  may  (as  in  the  case  of  low-trained  orange  trees)  suffice  to 
prevent  injury.  The  same  often  happens  in  the  case  of  low- trained 
vines,  small  fruit,  and  vegetables.  Sanding  of  the  surface  to  the  depth 
of  several  inches  was  among  the  first  attempts  in  this  direction;  but 
the  necessity  of  cultivation,  involving  the  renewal  of  the  sand  each 
season,  renders  this  a  costly  method.  Straw,  leaves,  and  manure  have 
been  more  successfully  used;  but  even  these,  unless  employed  for  the 
purpose  of  fertilization,  involve  more  expense  and  trouble  than  the  sim- 
ple maintenance  of  very  loose  tilth  of  the  surface  soil  throughout  the  dry 
season;  a  remedy  which,  of  course,  is  equally  applicable  to  field  crops, 
and  in  the  case  of  some  of  these — e.  g.,  cotton — is  a  necessary  condition 
of  cultural  success  everywhere.  The  wide  prevalence  of  "light"  and 
deep  soils  in  the  arid  regions,  from  causes  inherent  in  the  climate 
itself,*  renders  this  condition  of  relatively  easy  fulfilment. 

Diluting  the  Alkali  Salts. — Aside,  however,  from  the  mere  prevention 
of  surface  evaporation,  another  favorable  condition  is  realized  by  this 
procedure,  namely,  the  commingling  of  the  heavily  salt-charged  surface 
layers  with  the  relatively  nonalkaline  subsoil.  Since  in  the  arid 
regions  the  roots  of  all  plants  retire  farther  from  the  surface  because  of 
the  deadly  drought  and  heat  of  summer,  it  is  possible  to  cultivate 
deeper  than  could  safely  be  done  with  growing  crops  in  humid  climates. 
Yet  even  here,  the  maxim  of  "deep  preparation  and  shallow  cultiva- 
tion "  is  put  into  practice  with  advantage,  only  changing  the  measure- 
ments of  depth  to  correspond  with  the  altered  climatic  conditions. 
Thus,  while  in  the  eastern  United  States  four  inches  is  the  accepted  stand- 
ard of  depth  for  summer  cultivation  to  preserve  moisture  without 
injury  to  the  roots,  that  depth  must  in  the  arid  region  frequently  be 
doubled  in  order  to  be  effective,  and  will  even  then  scarcely  touch  a 
living  root  in  orchards  and  vineyards  in  unirrigated  land. 

A  glance  at  Fig.  1  (p.  7)  will  show  the  great  advantage  of  extra 
deep  preparation  in  commingling  the  alkali  salts  accumulated  near 
the  surface  with  the  lower  soil  layers,  diffusing  the  salts  through  12 
instead  of  6  inches  of  soil  mass.  This  will  in  very  many  cases  suffice 
to  render  the  growth  of  ordinary  crops  possible  if,  by  subsequent  fre- 
quent and  thorough  cultivation,  surface  evaporation,  and  with  it  the 
reascent  of  the  salts  to  the  surface,  is  prevented.  A  striking  example 
of  the  efficiency  pi  this  mode  of  procedure  was  given  at  the  Tulare 
substation,  where  a  portion  of  a  very  bad  alkali  spot  was  trenched  to 
the  depth  of  two  feet,  throwing  the  surface  soil  to  the  bottom.     The  spot 

*  See  reference  on  preceding  page. 


—  16  — 

thus  treated  produced  excellent  wheat  crops  for  a  few  years — the  time 
it  took  the  alkali  salts  to  reascend  to  the  surface. 

It  should  therefore  be  kept  in  mind  that  whatever  else  is  done  toward 
reclamation,  deep  preparation  and  thorough  cultivation  must  be  regarded 
as  prime  factors  for  the  maintenance  of  production  on  all  alkali  lands. 

The  efficacy  of  shading,  already  referred  to.  is  strikingly  illustrated 
in  the  case  of  some  field  crops  which,  when  once  established,  will 
thrive  on  fairly  strong  alkali  soil,  provided  that  a  good  thick  "stand''' 
has  once  been  obtained.  This  is  notably  true  of  the  great  forage  crop 
of  the  arid  region,  alfalfa,  or  lucern.  Its  seed  is  extremely  sensitive  to 
black  alkali,  and  will  decay  in  the  ground  unless  protected  against  it. 
But  when  once  a  full  stand  has  been  obtained,  the  field  may  endure  for 
many  years  without  a  sign  of  injury.  Here  two  effects  combine,  viz, 
the  shading,  and  the  evaporation  through  the  deep  roots  and  abundant 
foliage,  which  alone  prevents,  in  a  large  measure,  the  ascent  of  the 
moisture  to  the  surface.  The  case  is  then  precisely  parallel  to  that  of 
the  natural  soil  (see  Fig.  2),  except  that,  as  irrigation  is  practiced  in 
order  to  stimulate  production,  the  sheet  of  alkali  hardpan  will  be  dis- 
solved and  its  salts  spread  through  the  soil  more  evenly.  The  result  is 
that  oftentimes,  so  soon  as  the  alfalfa  is  taken  off  the  ground  and  the 
cultivation  of  other  crops  is  attempted,  an  altogether  unexpectedly  large 
amount  of  alkali  comes  to  the  surface  and  greatly  impedes,  if  it  does 
not  altogether  prevent,  the  immediate  planting  of  other  crops.  Shallow- 
rooted  annual  crops  that  give  but  little  shade,  like  the  cereals,  while 
measurably  impeding  the  rise  of  the  salts  during  their  growth,  fre- 
quently allow  of  enough  rise  after  harvest  to  prevent  reseeding  the 
following  season. 

Chemical  Remedies. 

Of  the  three  sodium  salts  that  usually  constitute  the  bulk  of  " alkali" 
only  the  carbonate  of  soda  is  susceptible  of  being  materially  changed 
by  any  agent  that  can  practically  be  applied  to  land.  So  far  as  we 
know,  the  salt  of  sodium  least  injurious  to  ordinary  vegetation  is  the 
sulphate,  commonly  called  glauber  salt,  which  ordinarily  forms  the 
chief  ingredient  of  white  alkali.  Thus  barley  is  capable  of  resisting 
about  five  times  more  of  the  sulphate  than  of  the  carbonate,  and  quite 
twice  as  much  as  of  common  salt.  Since  the  maximum  percentage  that 
can  be  resisted  by  plants  varies  materially  with  the  kind  of  soil,  it  is 
difficult  to  give  exact  figures  save  with  respect  to  particular  cases.  For 
the  sandy  loam  of  the  Tulare  substation  the  maximum  for  cereals  may 
be  approximately  stated  to  be  one  tenth  of  one  per  cent  (0.1)  for  sal- 
soda,  a  fourth  of  one  per  cent  (0.25)  for  common  salt,  and  from  forty-five 
to  fifty  one  hundredths  of  one  per  cent  (0.45-.50)  for  glauber  salt, 
within  the  first  foot  from  the  surface.  For  clay  soils  the  tolerance  is 
markedly  less,  especially  as  regards  the  salsoda,  since  in  their  case  the 


—  17  — 

injurious  effect  on  the  tilling  qualities  of  the  soil,  already  referred  to, 
is  superadded  to  the  corrosive  action  of  that  salt;  and  in  them,  more- 
over, accumulation  at  the  surface  is  more  pronounced. 

Since,  then,  so  little  carbonate  of  soda  suffices  to  render  soils  un- 
cultivable,  it  frequently  happens  that  its  mere  transformation  into 
the  sulphate  is  sufficient  to  remove  all  stress  from  alkali.  Gypsum 
(land-plaster)  is  the  cheap  and  effective  agent  to  bring  about  this 
transformation,  provided  water  be  also  present.  The  amount  required 
per  acre  will,  of  course,  vary  with  the  amount  of  carbonate  of  soda  in  the 
soil,  all  the  way  from  a  few  hundred  pounds  to  several  tons  in  the  case 
of  strong  alkali  spots.  But  it  is  not  usually  necessary  to  add  the  entire 
quantity  at  once,  provided  that  sufficient  be  used  to  neutralize  the  alkali 


Fig.  5.    Wheat  growing  in  soil  crusted  with  white  alkali,  originally  a  barren  black 
alkali  spot.    Tulare  Experiment  Substation. 

near  the  surface,  and  enough  time  be  allowed  for  the  action  to  take 
place.  In  very  wet  soils  this  may  occur  within  a  few  days;  in  merely 
damp  soils,  in  the  course  of  months;  but  usually  the  effect  increases  for 
years,  as  the  salts  rise  from  below.  For  the  complete  neutralization  of 
each  1,000  pounds  of  carbonate  of  soda  in  the  land,  1,630  pounds  of 
pure  gypsum  is  required.  But  of  the  impure,  80-85%  article  as  now 
on  the  market  in  California,  an  even  double  quantity,  or  2,000  pounds, 
would  be  the  proper  dose. 

The  effect  of  gypsum  on  the  black-alkali  soil  of   Tulare  substation 

was  to  change  a  barren  spot  into  a  tract  which  produced  a  fine  crop  of 

wheat,  although  the  surface  of  the  soil  was  covered  with  a  crust  of  the 

white  alkali  (sulphate  of  soda).     This  is  shown  in  the  accompanying 

hotograph  (Fig.  5). 

2-b128 


—  18  — 

The  effect  of  gypsum  on  black  alkali  land  is  often  very  striking,  even 
to  the  eye.  The  blackish  puddles  and  spots  disappear,  because  the 
gypsum  renders  the  dissolved  humus  insoluble  and  thus  restores  it  to 
the  soil.  The  latter  soon  loses  its  hard,  puddled  condition  and  crum- 
bles and  bulges  into  a  loose  mass,  into  which  water  now  soaks  freely, 
bringing  up  the  previously  depressed  spots  to  the  general  level  of  the 
land,  and  permitting  free  subdrainage.  On  the  surface  thus  changed 
seeds  now  germinate  and  grow  without  hindrance;  and  as  the  injury 
from  alkali  occurs  at  or  near  the  surface,  it  is  usually  best  to  simply 
harrow  in  the  plaster,  leaving  the  water  to  carry  it  down  in  solution. 
Soluble  phosphates  present  are  decomposed,  so  as  to  retain  finely 
divided  but  less  soluble  phosphates  in  the  soil. 

Trees  and  vines  already  planted  may  be  temporarily  protected  from 
the  worst  effects  of  the  black  alkali  by  surrounding  the  trunks  with 
gypsum  or  with  earth  abundantly  mixed  with  it.  Seeds  may  be  simi- 
larly protected  in  sowing,  and  young  plants  in  planting. 

It  must  not  be  forgotten  that  this  beneficial  change  may  go  back- 
ward if  the  land  thus  treated  is  permitted  to  be  swamped  by  excess  of 
irrigation  water,  or  otherwise.  Under  the  same  conditions,  naturally 
white  alkali  may  turn  black;  and  no  amount  of  gypsum  used  can  pre- 
vent or  undo  this  until  the  excess  of  water  is  drained  off  and  the  soil 
allowed  time  for  aeration.  Thus  while  excessive  irrigation  is  injurious 
at  all  times  in  diminishing  the  depth  of  root-growth  and  the  feeding 
area  of  the  plant,  it  is  especially  so  when  alkali  is  present.  Of  .course, 
gypsum  is  of  no  benefit  whatever  on  soils  containing  no  salsoda,  but 
only  glauber  and  common  salt. 

Stable  Manure  and  Other  Fertilizers. — Under  the  impression  that 
alkali  land  is  poor  in  plant-food,  farmers  frequently  try  applications  of 
stable  manure  and  other  fertilizers.  As  a  rule,  these  applications  are 
not  only  useless  but  even  harmful.  From  their  very  mode  of  formation, 
alkali  soils  are  exceptionally  rich  in  plant-food,  so  that  the  addition  of 
more  can  do  no  good.  In  the  case  of  stable  manure  being  used  on 
black  alkali  ground,  a  pungent  odor  of  ammonia  is  given  off  whenever 
the  sun  shines,  and  plants  otherwise  doing  well  are  thus  injured  or 
killed.  When  well  plowed-in,  stable  manure  will  sometimes  prevent 
to  some  extent  the  rise  of  alkali  by  diminishing  evaporation;  but  its 
usefulness  in  that  respect  is  readily  replaced  by  good  tillage.  The 
main  benefit  obtained  is  the  addition  of  humus  to  soils  that  have  been 
whitened  by  alkali  action. 

Potash  salts,  especially  kainit,  are  wholly  useless  and  add  to  the 
alkali  trouble;  potash  is  always  abundantly  present  in  alkali  lands, 
even  in  the  water-soluble  condition.  Nitrates,  also,  are  always  present 
in  alkali  soils  in   sufficient  amounts  for  plant  growth,  sometimes  to 


—  19  — 

excess.  Phosphates  may  sometimes  be  useful,  but  will  rarely  be  needed 
for  some  years.  Greenmanuring,  on  the  other  hand,  is  a  very  desirable 
improvement  on  all  alkali  lands. 

Removing  the  Salts  from  the  Soil. 

In  case  the  amount  of  salts  in  the  soil  should  be  so  great  that  even 
the  change  worked  by  gypsum  is  insufficient  to  render  it  available  for 
useful  crops,  the  only  remedy  left  is  to  remove  the  salts  partially  or 
wholly  from  the  land.  Two  chief  methods  are  available  for  this  purpose. 
One  is  to  remove  the  salts,  with  more  or  less  earth,  from  the  surface  at 
the  end  of  the  dry  season,  either  by  sweeping,  or  by  means  of  a  horse 
scraper  set  so  as  to  carry  off  a  certain  depth  of  soil.  Thus  sometimes 
in  a  single  season  one  third  or  one  half  of  the  total  salts  may  be  got 
rid  of,  the  loss  of  a  few  inches  of  surface  soil  being  of  little  moment  in 
the  deep  soils  of  the  arid  region.  The  other  method  is  to  leach  them 
out  of  the  soil  into  the  country  drainage,  supplementing  by  irrigation 
water  what  is  left  undone  by  the  deficient  rainfall. 

It  is  not  practicable,  as  many  suppose,  to  wash  the  salts  off  the  sur- 
face by  a  rush  of  water,  as  they  instantly  soak  into  the  ground  at  the 
first  touch.  Nor  is  there  any  sensible  relief  from  allowing  the  water  to 
stand  on  the  land  and  then  drawing  it  off;  in  this  case  also  the  salts 
soak  down  ahead  of  the  water,  and  the  water  standing  on  the  surface 
remains  almost  unchanged.  In  very  pervious  soils,  and  in  the  case  of 
white  alkali,  the  washing-out  can  often  be  accomplished  without  special 
provision  for  underdrainage,  by  leaving  the  water  on  the  land  suffi- 
ciently long.  But  the  laying  of  regular  underdrains  greatly  accelerates 
the  work,  and  renders  success  certain. 

An  important  exception,  however,  occurs  in  the  case  of  black  alkali 
in  most  lands.  In  this  case  either  the  impervious  hardpan  or  (in  the 
case  of  actual  alkali  spots)  the  impenetrability  of  the  surface  soil  itself, 
will  render  even  underdrains  ineffective  unless  the  salsoda  and  its 
effects  on  the  soil  are  first  destroyed  by  the  use  of  gypsum,  as  above 
detailed.  This  is  not  only  necessary  in  order  to  render  drainage  and 
leaching  possible,  but  is  also  advisable  in  order  to  prevent  the  leaching- 
out  of  the  valuable  humus  and  soluble  phosphates,  which  are  rendered 
insoluble  (but  not  unavailable  to  plants)  by  the  action  of  the  gypsum. 
Wherever  black  alkali  is  found,  therefore,  the  application  of  gypsum 
should  precede  any  and  all  other  efforts  toward  reclamation. 

Another  method  for  diminishing  the  amount  of  alkali  in  the  soil  is 
the  cropping  with  plants  that  take  up  considerable  amounts  of  salts. 
In  taking  them  into  cultivation,  it  is  advisable  to  remove  entirely  from 
the  land  the  salt  growth  that  may  naturally  cover  it,  notably  the 
greasewoods  (Allenrolfea,  Sarcobatus),  with  their  heavy  percentages  of 
alkaline  ash.  Crop  plants  adapted  to  the  same  object  are  mentioned 
farther  on. 


—  20  — 
Will  It  Pay  to  Reclaim   Alkali  Lands? 

This  is  a  question  naturally  asked  when  considering  the  nature  and 
expense  of  the  operation  involved,  especially  when  the  last  resort — 
underdraining  and  leaching— has  to  be  adopted. 

Those  familiar  with  the  alkali  regions  are  aware  how  often  the 
occurrence  of  alkali  spots  interrupts  the  continuity  of  fields  and 
orchards,  of  which  they  form  only  a  small  part,  but  enough  to  mar  their 
aspect  and  cultivation.  Their  increase  and  expansion  under  irrigation 
frequently  render  their  reclamation  the  only  alternative  of  absolute 
abandonment  of  the  investments  and  improvements  made,  and  from 
that  point  of  view  alone  it  is  of  no  slight  practical  importance.  More- 
over, the  occurrence  of  vast  continuous  stretches  of  alkali  lands  within 
the  otherwise  most  eligibly  situated  portions  of  the  irrigation  region 
forms  a  strong  incentive  toward  their  utilization. 

There  is,  however,  a  strong  intrinsic  reason  pointing  in  the  same 
direction,  namely,  the  almost  invariably  high  and  lasting  productive- 
ness of  these  lands  when  once  rendered  available  to  agriculture.  This  is 
foreshadowed  by  the  usually  very  heavy  and  luxuriant  growth  of  native 
plants  around  the  margins  of  and  between  alkali  spots  (see  Fig.  6); 
that  is,  wherever  the  amount  of  injurious  salts  present  is  so  small  as  not 
to  interfere  with  the  utilization  of  the  abundant  store  of  plant-food  which, 
under  the  peculiar  conditions  of  soil  formation  in  arid  climates,  remains 
in  the  land  instead  of  being  washed  into  the  ocean.  Extended  com- 
parative investigations  of  soil  composition,  as  well  as  the  experience  of 
thousands  of  years  in  the  oldest  settled  countries  of  the  world,  demon- 
strate this  fact  and  show  that  so  far  from  being  in  need  of  fertilization, 
alkali  lands  possess  extraordinary  productive  capacity  whenever  freed 
from  the  injurious  influence  of  the  excess  of  useless  salts  left  in  the  soil 
in  consequence  of  deficient  rainfall.  Alkali  salts  are  actually  scraped 
up  and  carried  to  the  cultivated  fields  in  sacks  in  parts  of  Turkestan, 
the  peasants  considering  that  "  the  salt  is  the  life  of  the  land."  (Mid- 
dendorf). 

It  does  not,  of  course,  follow  that  alkali  lands  are  good  lands  for 
farmers  of  limited  means  to  settle  upon.  On  the  contrary,  like  most 
other  business  enterprises,  they  require  a  certain  amount  of  capital  and 
lapse  of  time  to  render  them  productive.  They  are  not  therefore  a 
proper  investment  for  farmers  or  settlers  of  small  means,  dependent  on 
annual  crops  for  their  livelihood  and  unable  to  bring  to  bear  upon  these 
soils  the  proper  means  for  their  reclamation;  unless,  indeed,  local  con- 
ditions should  enable  them  to  use  successfully  some  of  the  crops  specially 
adapted  to  alkali  lands. 


-—  22  — 

Crops  Suitable  for  Alkali  Lands. 

As  has  already  been  stated,  the  search  for  generally  available  crops 
that  will  thrive  in  strong,  unreclaimed  alkali  land  has  not  thus  far 
been  very  successful.  It  is  true  that  cattle  will  nibble  alkali  grass 
(Distichlis  spicata),  but  will  soon  leave  it  for  any  dry  feed  that  may  be 
within  reach.  The  same  is  true  of  all  the  fleshy  plants  that  grow  on 
the  stronger  alkali  lands,  and  are  known  under  the  general  designa- 
tion of  alkali  weeds.  When  stock  unaccustomed  to  it  are  forced  by 
hunger  to  feed  on  such  vegetation  to  any  considerable  extent,  disor- 
dered digestion  is  apt  to  result;  which  in  such  ranges,  however,  is  often 
counteracted  by  feeding  on  aromatic  or  astringent  antidotes,  such  as 
the  gray  sagebrush  and  the  more  or  less  resinous  herbage  of  plants  of 
the  sunflower  family.  In  the  Great  Basin  region,  lying  between  the 
Sierra  Nevada  and  the  front  range  of  the  Rocky  Mountains,  there  are, 
aside  from  the  grasses,  numerous  herbaceous  and  shrubby  plants  that 
afford  valuable  pasturage  for  stock,*  and  some  of  these  grow  on  mod- 
erately strong  alkali  land;  the  same  is  true  in  California.  It  is  quite 
possible  that  some  of  these  will  be  found  to  lend  themselves  to  ready 
propagation  for  culture  purposes  as  well  as  they  do  for  restocking  the 
ranges.  But  thus  far  none  have  found  wider  acceptance,  probably 
because  their  stiff  branches  and  upright  habit  render  them  inconven- 
ient to  handle.  It  will  require  more  extended  experience  and  experi- 
ment before  any  of  these  can  be  definitely  adopted  by  farmers. 

Experience  in  California  indicates  that  in  the  more  southerly  portion 
of  the  arid  region  the  unpalatable  native  plants  may  be  generally 
replaced,  even  on  the  ranges,  by  one  or  more  species  of  the  Australian 
saltbushes  (Atriplex  spp.),  long  ago  recommended  by  Baron  von 
Mueller  of  Melbourne;  of  which  one  {A.  semibaccata)  has  proved  emi- 
nently adapted  to  the  climate  and  soil  of  California  and  is  readily 
eaten  by  all  kinds  of  stock.  The  facility  with  which  it  is  propagated, 
its  quick  development,  the  large  amount  of  feed  yielded  on  a  given 
area,  even  in  the  strongest  alkali  land  ordinarily  found,  and  its  thin, 
flexible  stems,  permitting  it  to  be  handled  very  much  like  alfalfa, 
seem  to  commend  it  specially  to  the  farmer's  consideration  wherever 
the  climate  will  permit  of  its  use.  Its  resistance  to  severe  cold  weather 
has  not  yet  been  adequately  tested.  It  is  probable  that  other  species, 
now  also  under  trial,  will  equally  justify  the  recommendation  given 
them  by  the  eminent  botanist  who  first  brought  them  into  public 
notice  as  promising  forage  plants.  Most  of  the  species  have  an  upright, 
shrubby  habit,  which  adapts  them  rather  to  browsing  than  to  use  as  a 

*  See  Bulletin  No.  16  of  the  Wyoming  Experiment  Station;  also  Bulletins  Nos.  2  and 
12  of  the  Division  of  Agrostology,  and  Farmers'  Bulletin  No.  108,  TJ.  S.  Department  of 
Agriculture. 


—  23  — 

forage  crop.  Among  the  best  next  to  the  semibaccata  are  the  species 
leptocarpa  and  halimoides,  the  former  somewhat  similar  in  habit  to  the 
semibaccata  but  not  so  rapid  a  grower.  A  special  bulletin  on  the  salt- 
bushes,  Australian  as  well  as  native,  has  been  published  by  this  Sta- 
tion and  will  be  sent  on  request. 

It  is  to  be  noted  that  since  the  saltbushes  take  up  nearly  one  fifth  of 
their  dry  weight  of  ash  ingredients*,  largely  common  salt,  the  complete 
removal  from  the  land  of  a  five-ton  crop  of  saltbush  hay  will  take  away 
nearly  a  ton  of  the  alkali  salts  per  acre.  This  will  in  the  course  of 
some  years  be  quite  sufficient  to  reduce  materially  the  saline  contents 
of  the  land,  and  wiU  frequently  render  possible  the  culture  of  ordinary 
crops. 

Next  to  the  saltbushes  the  Chilean  plant  Modiola  decumbens  (now 
commonly  known  as  modiola  simply),  of  the  mallow  family,  deserves 
attention.  Accidentally  introduced  as  a  weed  with  other  seeds,  by  the 
Kern  County  Land  Company  at  Bakersfield,  it  attracted  attention  by 
its  persistence  on  alkali  lands,  and  by  the  observation  that  cattle  ate  it 
freely.  It  was  then  grown  on  a  larger  scale,  and  found  to  make  accep- 
table pasture  where  alfalfa  could  not  be  grown  on  account  of  alkali.  It 
is  a  trailing  plant  with  medium-sized,  roundish  foliage,  and  roots  freely 
at  the  joints  where  they  touch  the  ground.  Unlike  the  saltbushes  it  is 
therefore  a  formidable  weed  where  it  is  not  wanted;  but  as  according  to 
our  determinations  it  resists  as  much  as  52,000  pounds  of  salts  per  acre, 
even  when  41,000  of  these  is  common  salt,  it  is  likely  to  be  useful  in 
many  cases,  particularly  as  an  admixture  to  a  saltbush  diet  for  stock, 
the  more  as  it  does  not  absorb  as  much  salt  as  the  latter.  Owing  to 
the  rooting  habit  of  the  stems,  it  is  not  as  convenient  to  handle  as  the 
semibaccata  saltbush,  nor,  probably,  will  it  yield  as  much  fodder  in  a 
season.     It  seems  best  adapted  to  pasturage. 

Another  forage  plant  which  it  may  hereafter  pay  to  propagate  arti- 
ficially on  strong  alkali  land,  is  the  tussock-grass  (Sporobolus  airoides), 
of  which  a  figure  is  given  on  page  37.  Indicating  as  it  usually  does 
when  growing  naturally,  land  too  strongly  impregnated  to  be  reclaimable 
at  this  time,  but  being  freely  eaten  by  stock,  it  seems  worth  while  to 
count  it  among  the  possible  pasture  grasses  for  land  too  strongly  alka- 
line to  bear  ordinary  crops.  Its  seed  can  be  abundantly  gathered  in  its 
native  habitats,  indicated  below. 


*  Analyses  made  at  the  California  station  show  19.37  per  cent  of  ash  in  the  air-dry 
matter  of  Australian  saltbush.  (See  California  Sta.  Bui.  105;  E.  S.  R.,  vol.  6,  p.  718.) 
Analyses  of  Russian  thistle  have  been  reported  showing  over  20  per  cent  of  ash  in  dry 
matter.    (See  Minnesota  Sta.  Bui.  34;  Iowa  Sta.  Bui.  26;  E.  S.  R.,  vol.  6,  pp.  552,  553.) 


—  24  — 

Amount  of  Salts  Compatible  with  Ordinary  Crops. 

Since  the  amount  of  alkali  that  reaches  the  surface  layer  is  largely- 
dependent  upon  the  varying  conditions  of  rainfall  or  irrigation  and 
surface  evaporation,  it  is  difficult  to  foresee  to  what  extent  that 
accumulation  may  go,  unless  we&  know  the  total  amount  of  salts  present 
that  may  be  called  into  action.  This  can  be  ascertained  by  a  summa- 
tion of  the  results  obtained  and  shown  in  the  above  diagrams  for  each 
layer,  but  more  readily  by  the  examination  of  one  sample  representing 
the  average  of  the  entire  soil  column  of  4  feet.  By  calculating  the 
figures  so  obtained  to  an  acre  of  ground,  we  can  at  least  approximate 
the  limits  within  or  beyond  which  crops  will  succeed  or  perish. 

Grasses. — Applying  this  procedure  to  the  cases  investigated  at  the 
Tulare  substation,  and  estimating  the  weight  of  the  soil  per  acre-foot  at 
4,000,000  pounds,  we  find  for  the  land  on  which  barley  refused  to  grow 
the  figure  32,480  pounds  of  total  salts  per  acre,  corresponding  to  0.203 
per  cent;  while  for  the  land  on  which  barley  gave  a  full  crop  we  find 
25,440  pounds,  equivalent  to  0.159  per  cent  for  the  whole  soil  column 
of  4  feet.  It  thus  appears  that  for  barley  the  limits  of  tolerance  lie 
between  the  above  two  figures,  which  might,  of  course,  have  been 
obtained  equally  well  from  an  average  sample  of  the  4-foot  column  by 
making  a  single  analysis.  It  should  be  noted  that  in  this  case  a  full 
crop  of  barley  was  grown  even  when  the  alkali  consisted  of  fully  one 
half  of  the  noxious  carbonate  of  soda,  proving  that  it  is  not  necessary 
in  every  case  to  neutralize  the  entire  amount  of  that  salt  by  means  of 
gypsum,  which  in  the  present  case  would  have  required  about  9i  tons 
of  gypsum  per  acre — a  prohibitory  expenditure. 

Rye  appears  to  be  about  like  barley  in  its  tolerance  of  alkali  salts; 
while  wheat  is  somewhat  more  sensitive.  In  fact,  the  superficial  rooting 
and  fine  fibrous  roots  of  the  true  grasses  render  them,  as  a  whole,  rather 
sensitive  to  alkali  salts;  yet  there  are  a  number  of  the  perennial  kinds 
whose  thick  roots  and  deeper  rooting  render  them  measurably  resistant. 
Aside  from  the  alkali  grass  proper  (Distichlis),  the  so-called  rye  grass 
of  the  Northwest  (Elymus  condensatus)  is  probably,  next  to  the  tussock- 
grass,  the  most  resistant  species  among  the  wild  grasses.  Its  southern 
form,  with  several,  others  not  positively  identified,  occupy  largely  the 
milder  alkali  lands  of  Southern  California,  such  as  the  low  lands  near 
Chino  producing  choice  sugar  beets  on  a  close-textured  silty  loam. 

While  maize  is  rather  sensitive,  and  fails  on  even  slightly  alkaline 
lands,  Egyptian  corn  and  other  sorghums,  rooting  somewhat  deeper, 
and  having  stout  roots,  do  well  on  mild  alkali  soils  of  the  white  class. 
The  same  appears  to  be  true  of  some  of  the  stout-rooted  millets,  such 
as  barnyard  grass  (Panicum  crus-galli),  of  which  the  variety  (?)  muti- 


—  25  — 

cum  is  reported  to  succeed  well  in  neutral  alkali  land.  One  of  the  most 
successful  grasses  on  the  light  alkali  lands  near  Chino,  where  most  of 
the  commonly  cultivated  kinds  fail,  was  a  near  relative  of  the  barnyard 
grass,  the  Eleusine  coracana,  which  produces  heavy  crops  of  a  millet- 
like grain  much  relished  by  poultry  and  also  by  stock.  This  grass  (of 
which  seed  can  be  obtained  from  the  Station)  has  succeeded  all  over 
the  ground  whose  alkali  content  ranges  up  to  12,000  pounds  per  acre. 
Next  to  this,  in  point  of  success,  were  the  pearl  millet  (Pennisetum 
typhoideum)  and  teosinte,  Hungarian  brome  grass,  and  Japanese  millet, 
on  land  containing  about  9,000  pounds  of  salts  per  acre.  The  loliums, 
including  the  darnel  ("  California  cheat"),  and  the  Australian  and 
Italian  ray  ("rye")  grasses,  succeed  fairly  on  land  containing  as  much  as 
6,000  pounds  of  (white)  salts.  Most  other  cultivated  grasses  failed 
conspicuously  alongside  of  these.  It  must  be  remembered  that  in  more 
loose-textured,  sandy  lands  than  those  in  which  these  tests  were  made, 
the  above  figures  for  tolerance  would  probably  be  increased  by  30  per 
cent  or  more. 

Doubtless  some  of  the  indigenous  grasses  of  the  interior  plateau 
region  and  the  great  plains  east  of  the  Rocky  Mountains,  such  as  the 
buffalo  and  grama  grasses,  as  well  as  several  of  the  wheat  grasses 
(Agropyron)  and  bunch  grasses  (Festuca,  Poa,  Stipa,  etc.)  will  prove 
resistant  to  larger  proportions  of  alkali  than  the  meadow  and  pasture 
grasses  of  the  regions  of  summer  rains. 

Legumes. — Both  the  natural  growth  of  alkali  lands  and  experimental 
tests  seem  to  show  that  this  entire  family  (peas,  beans,  clovers,  etc.) 
are  among  the  more  sensitive  and  least  available  wherever  black  alkali 
exists,  while  fairly  tolerant  of  the  white  (neutral)  salts.  Apparently  a 
very  little  salsoda  suffices  to  destroy  the  tubercle-forming  organisms  that 
are  so  important  a  medium  of  nitrogen-nutrition  in  these  plants.  Alfalfa, 
with  its  hard,  stout,  and  long  taproot,  seems  to  resist  best  of  all  these 
plants,  excepting  the  melilots.  As  a  general  thing,  taprooted  plants, 
when  once  established,  resist  best,  for  the  obvious  reason  that  the  main 
mass  of  their  feeding  roots  reaches  below  the  danger  level.  Another  favor- 
ing condition,  already  alluded  to,  is  heavy  foliage  and  consequent  shad- 
ing of  the  ground;  alfalfa  happens  to  combine  both  of  these  advantages. 
There  has  been  some  difficulty  in  obtaining  a  full  stand  of  alfalfa  in  the 
portion  of  the  Chino  tract  containing  from  4,000  to  6,000  pounds  of  alkali 
salts  per  acre;  but  once  obtained  it  has  done  very  well.  The  only  other 
plant  of  this  family  that  succeeds  well  on  this  land,  and  even  (at  Tulare) 
on  soil  considerably  stronger  (probably  between  20,000  and  30,000 
pounds)  are  the  two  melilots,  M.  indica  and  alba;  the  latter  (the 
Bokhara  clover)  is  a  forage  plant  of  no  mean  value  in  moist  climates, 
but  somewhat  restricted  in  its  use  in  California  because  of  the  very  high 
aroma  it  develops,  especially  in  alkali  lands;  so  that  stock  will  eat  only 


—  26  — 

limited  amounts,  best  when  intermixed  with  other  forage,  such  as  the 
saltbushes.  The  yellow  melilot  is  highly  recommended  by  the  Arizona 
station  as  a  greenmanure  plant  for  winter  growth;  but  in  this  State  it 
is  a  summer-growing  plant  only,  and  is  refused  by  stock.  Very  few 
plants  belonging  to  this  famity  are  naturally  found  on  alkali  lands,  and 
attempts  to  grow  them,  even  where  only  glauber  salt  is  present,  have 
been  but  very  moderately  successful.  The  salts  seem  to  retard  or  even 
prevent  the  formation  of  the  tubercles  useful  for  nitrogen  absorption; 
and  for  most  of  the  legumes  the  limit  of  full  success  seems  to  lie  between 
3,000  and  4,000  pounds  to  the  acre. 

Weeds. — Like  the  legumes,  wild  plants  of  the  mustard  family  are  rare 
on  alkali  lands;  and  correspondingly,  the  cultivated  mustard,  kale,  rape, 
etc.,  fail  even  on  land  quite  weak  in  alkali.  Their  limit  of  tolerance 
seems  to  lie  near  4,000  to  5,000  pounds  per  acre  of  even  white  salts. 

Several  of  the  hardiest  of  the  native  "alkali  weeds"  belong  to  the  sun- 
flower family,  and  the  common  wild  sunflowers  (Helianthus  californicus 
and  H.  annuus)  are  common  on  lands  pretty  strongly  alkaline.  Cor- 
respondingly, the  "  Jerusalem  artichoke,"  itself  a  sunflower,  is  among 
the  available  crops  on  moderately  strong  alkali  soils;  and  so,  doubtless, 
are  other  members  of  the  same  relationship  not  yet  tested,  such  as  the 
true  artichoke,  salsify,  etc.  Chicory,  belonging  to  the  same  family, 
yielded  roots  at  the  rate  of  12  tons  per  acre,  on  land  on  the  Chino  tract 
containing  about  8,000  pounds  of  salts  per  acre. 

Root  Crops. — It  seems  to  be  generally  true  that  root  crops  suffer  in 
quality,  however  satisfactory  may  be  the  quantity  harvested  on  lands 
rich  in  salts,  and  especially  in  chlorids  (common  salt).  It  was  noted  at 
the  Tulare  substation  that  the  tubers  of  the  artichoke  were  inclined  to 
be  "squashy"  in  the  stronger  alkali  land,  and  failed  to  keep  well;  the 
same  was  true  of  potatoes,  which  were  very  watery;  and  also  of  turnips 
and  carrots.  It  is  a  fact  well  known  in  Europe,  that  potatoes  manured 
with  kainit  (chlorids  of  potassium  and  sodium)  are  unfit  for  the  man- 
ufacture of  starch,  and  are  generally  of  inferior  quality.  But  this  is 
found  not  to  be  the  case  when,  instead  of  the  chlorids,  the  sulphate  is 
used;  hence  the  advice,  often  repeated  by  this  Station,  that  farmers 
desiring  to  use  potash  fertilizers  should  call  for  the  "  high-grade  sul- 
phate" instead  of  the  cheaper  kainit,  which  adds  to  the  injurious  salts 
already  so  commonly  present  in  California  lowland  soils. 

The  common  beet  (including  the  mangel-wurzel)  is  known  to  succeed 
well  on  saline  seashore  lands,  and  it  maintains  its  reputation  on  alkali 
lands  also.  Being  specially  tolerant  of  common  salt,  it  may  be  grown 
where  other  crops  fail  on  this  account;  but  the  roots  so  grown  are 
strongly  charged  with  common  salt,  and  have,  as  is  well  known,  been 


—  27  — 

used  for  the  purpose  of  removing  excess  of  the  same  from  marsh  lands. 
Such  roots  are  wholly  unfit  for  sugar-making. 

It  is  quite  otherwise  with  glauber  salt  (sodium  sulphate);  and  as 
this  is  usually  predominant  in  alkali  lands,  either  before  or  after  the 
gypsum  treatment,  this  fact  is  of  great  importance,  for  it  permits  of  the 
successful  growing  of  the  sugar  beet;  as  has  been  abundantly  proved  at 
the  Chino  ranch,  where  land  containing  as  much  as  12,000  pounds  of 
salts,  mostly  this  compound,  has  yielded  roots  of  very  high  grade  both 
as  to  sugar  percentage  and  purity. 

Asparagus  is  another  crop  which  bears  considerable  amounts  of  com- 
mon salt  as  well  as  of  glauber  salt;  but  not  of  salsoda,  which  must 
first  be  transformed  by  the  use  of  gypsum. 

Rhubarb  was  a  conspicuous  failure  in  even  the  weak  alkali  lands  of 
the  Chino  tract. 

Textile  Plants. — Japanese  hemp  seemed  to  have  a  hard  struggle 
with  the  alkali  while  young,  but  at  the  end  of  the  season  stood  8  feet 
high.  The  ramie  plant,  also,  will  bear  moderately  strong  alkali,  appar- 
ently somewhat  over  12,000  pounds  per  acre.  Flax  has  not  been  tested 
in  cultivation;  but  its  wide  distribution  all  over  the  States  of  Oregon 
and  Washington  would  seem  to  indicate  that  it  is  not  very  sensitive. 
Another  textile  plant,  the  Indian  mallow  (Abutilon  avicennm),  was 
found  to  fail  on  the  Chino  alkali  soil. 

Grapevines. — The  Vitis  vinifera  is  quite  tolerant  of  white  or  neutral 
alkali  salts,  and  will  resist  even  a  moderate  amount  of  the  black  so 
long  as  no  hardpan  is  allowed  to  form.  At  the  Tulare  substation,  it 
was  found  that  grapevines  did  well  in  sandy  land  containing  35,230 
pounds  of  alkali  salts,  of  which  one  half  was  glauber  salt,  9,640  pounds 
carbonate  of  soda,  7,550  pounds  common  salt,  and  750  pounds  nitrate  of 
soda.  They  were  badly  distressed  where,  of  a  total  of  37,020  pounds  of 
alkali  salts,  25,620  pounds  was  carbonate  of  soda;  while  where  the 
vines  had  died  out,  there  was  found  a  total  of  73,930  pounds,  with 
37,280  pounds  of  carbonate.  The  European  vine,  then,  is  considerably 
more  resistant  of  alkali,  even  in  its  worst  (black)  form,  than  barley 
and  rye;  and  it  seems  likely  that  the  native  grapevines  of  the  Pacific 
Coast,  Calif ornica  and  Arizonica,  would  resist  even  better;  a  point  still 
under  experiment. 

Experience,  however,  has  shown  that  vines  rapidly  succumb  when  by 
excessive  irrigation  the  bottom  water  is  allowed  to  rise,  increasing  the 
amount  of  alkali  salts  near  the  surface  and  shallowing  the  soil  at  their 
disposal.  Such  over-irrigation  has  been  a  fruitful  cause  of  injury  to 
vineyards  in  the  Fresno  region,  and  would  doubtless  if  practiced  kill 
most  of  the  vines  at  Tulare  substation  which  are  now  flourishing.  In 
such  cases  sometimes  the  formation  of  hardpan  is  followed  by  that  of  a 


—  28  — 

concentrated  alkaline  solution  above  it,  strong  enough  to  corrode  the 
roots  themselves,  and  not  only  killing  the  vines,  but  rendering  the  land 
unfit  for  any  agricultural  use  whatsoever.  The  swamping  of  alkali 
lands,  whether  of  the  white  or  black  kind,  is  not  only  fatal  to  their 
present  productiveness,  but,  on  account  of  the  strong  chemical  action 
thus  induced,  greatly  jeopardizes  their  future  usefulness.  Many  costly 
investments  in  orchards  and  vineyards  have  thus  been  rendered  unpro- 
ductive, or  have  even  become  a  total  loss. 

Citrus  Trees. — These  are  on  the  whole  rather  sensitive  to  alkali, 
especially  while  young;  so  that  it  is  often  difficult  to  obtain  a  stand  even 
when,  later  on,  the  feeding  roots  descend  beyond  the  reach  of  injury. 
In  the  close-textured  lands  of  Chino,  young  trees  hardly  maintained 
life  with  more  than  5,000  pounds  of  total  salts.  Common  salt  seems  to 
be  particularly  injurious;  near  Riverside,  full-grown  trees  perished 
under  the  influence  of  bottom  water  containing  0.25  per  cent  or  146 
grains  of  salt  per  gallon,  which  impregnated  the  ground;  corresponding 
to  about  9,000  pounds  per  acre  in  four  feet. 

In  the  sandy  loam  lands  near  Corona,  trees  eight  years  old  suffered 
severely  when  by  irrigation  with  alkali  water  the  alkali  content  of  the 
land  reached  11,000  pounds  per  acre;  as  illustrated  in  Plates  7  and  8, 
pages  32  and  33.  At  another  point  in  the  same  region,  two  representa- 
tive trees  were  selected  for  comparison,  five  rows  apart  on  land  absolutely 
identical;  one  of  these  retained  its  leaves,  though  suffering,  the  other 
was  completely  leafless.  The  leaching  of  the  alkali  to  the  depth  of  4  feet 
gave  the  following  results,  calculated  to  pounds  per  acre: 

Sulphates.    Carbonates.    Chlorids.    Total. 

Poortree 4,720  1,680  2,520        8,920 

Better  tree _ 4,120  2,360  720        7,200 

Here  it  is  apparently  the  excess  of  common  salt  to  which  the  differ- 
ence is  due,  and  this  despite  the  higher  content  of  carbonate  of  soda  in 
the  soil  bearing  the  better  tree. 

On  the  other  hand,  at  the  Tulare  substation,  orange  trees  (sour  stock) 
maintain  vigorous  growth  and  good  bearing  in  a  very  sandy  tract 
which  to  the  depth  of  7  feet  showed  an  aggregate  content  of  26,840 
pounds  of  salts  (or  22,780  to  4  feet  depth);  but  which  is  never  irri- 
gated. (See  diagram,  page  10.)  The  salts  in  this  case  consist  wholly 
of  sulphate  and  carbonate  of  soda  in  the  ratio  of  54  to  42,  implying 
the  presence  of  nearly  12,000  pounds  of  salsoda  within  reach  of  the 
tree  roots;  yet  in  the  absence  of  common  salt,  no  perceptible  injury  or 
even  stress  upon  the  trees  has  been  noted. 

In  view  of  these  facts,  it  seems  that  common  salt  is  the  portion  of 
alkali  by  far  most  injurious  to  citrus  trees,  and  that  great  care  should 
be  taken  in  the  use  of  irrigation  waters  to  exclude  those  charged  with 


—  29  — 

common  salt;    also,  to  avoid  locating  citrus  orchards  where  common 
salt  pre-exists  in  the  land. 

Deciduous  Orchard  Trees. — Of  these,  strangely  enough,  the  almond 
seems  to  resist  best.  The  peach  is  more  sensitive;  the  apricot  does  fairly. 
Plum  trees  as  such  are  nearly  as  resistant  as  peaches,  but  sometimes  sud- 
denly begin  to  fail  when  beginning  to  bear;  the  fruit  appears  normal  on 
the  outside  for  a  time,  but  the  pit  fails  to  form,  being  sometimes  flattened 
out  like  a  piece  of  pasteboard;  and  the  fruit  fails  to  mature.  Apples 
are  rather  sensitive;  pears  considerably  less  so,  doing  well  even  when 
the  outside  bark  around  the  root  crown  is  blackened  by  the  alkali.  The 
olive  is  quite  resistant;  the  fig  less  so.  The  English  walnut  resents 
even  a  slight  taint  of  black  alkali,  but  is  fairly  tolerant  of  "white" 
salts,  as  is  shown  in  the  peculiarly  suitable  light  loam  soils  on  the 
lower  Santa  Clara  River,  in  Ventura  County. 

Figures  for  the  limits  of  alkali  tolerance  in  the  case  of  the  deciduous 
orchard  trees  have  not  yet  been  closely  determined,  owing  to  the 
difficulties  inherent  in  the  differences  of  root  penetration  in  the  several 
soils  and  localities.  On  the  ten-acre  tract  near  Chino,  therefore  on 
a  rather  close-textured  soil,  apple  trees  have  done  very  well  on  land 
containing  one  fourth  of  one  per  cent  of  ("white")  salts,  or  between 
10,000  and  11,000  pounds  per  acre.  On  similar  soil,  the  quince  appears 
to  be  perfectly  at  home. 

Timber  and  Shade  Trees. — Of  trees  suitable  for  alkali  lands,  two  native 
ones  call  for  mention.  One  is  the  California  white  or  valley  oak  ( Quercus 
lobata),  which  forms  a  dense  forest  of  large  trees  on  the  delta  lands  of 
the  Kaweah  River  in  California,  and  is  found  scatteringly  all  over  the 
San  Joaquin  Valley  (see  frontispiece).  Unfortunately,  this  tree  does  not 
supply  timber  valuable  for  aught  but  firewood  or  fence  posts,  being 
quite  brittle.  The  native  cottonwoods,  while  somewhat  retarded  and 
dwarfed  in  their  growth  in  strong  alkali,  are  quite  tolerant  of  the  white 
salts,  especially  of  glauber  salt. 

Of  other  trees,  the  oriental  plane,  or  sycamore,  and  the  black  locust, 
have  proved  the  most  resistant  in  the  alkali  lands  of  the  San  Joaquin 
Valley;  and  the  former  being  a  very  desirable  shade  tree,  it  should  be 
widely  used  throughout  the  regions  where  alkali  prevails  more  or  less. 
The  ailantus  is  about  equally  resistant,  and  but  for  the  evil  odor  of  its 
flowers,  deserves  strong  commendation.  Of  the  eucalypts,  the  narrow- 
leaved  Eucalyptus  amygdalina  (one  of  the  "red  gums")  seems  to  be 
least  sensitive,  and  in  some  cases  has  grown  as  rapidly  as  anywhere. 
The  E.  rostrata,  as  well  as  the  pink-flowered  variety  of  E.  sideroxylon, 
are  now  doing  about  as  well  as  the  amygdalina  at  Tulare,  where  at  first 
they  seemed  to  suffer.  The  common  blue  gum,  E.  globulus,  is  much 
more  sensitive. 


—  30  - 

Of  the  acacias,  the  tall-growing  A,  melanoxylon  ("  black  acacia ") 
resists  pretty  strong  alkali,  even  on  stiff  soil;  as  can  be  seen  at  Tulare 
and  Bakersfield,  where  there  are  trees  nearly  two  feet  in  diameter.  The 
beautiful  A.  lophantha  (Albizzia)  has  in  plantings  made  along  the  San 
Joaquin  Valley  Railroad  shown  considerable  resistance,  likewise;  but 
it  is  quite  sensitive  to  frost. 

One  of  the  "Australian  pines,  Casuarina  equisetifolia"  was  transplanted 
experimentally  on  station  grounds  of  the  Valley  Railroad  from  the 
Chico  forestry  substation,  and  a  number  are  growing  very  well  in  alkali 
lands.  This  tree  is  credited  by  Maiden  with  being  tolerant  of  "saline 
soil."  Doubtless  many  others  of  the  Casuarina  tribe  will  be  found  sim- 
ilarly resistant. 

Of  Eastern  trees,  the  elms  have  done  fairly  well,  but  the  tulip  tree, 
the  linden,  the  English  oak,  and  most  other  trees  of  the  Atlantic  States, 
become  stunted.  Among  those  doing  fairly  well  is  the  honey  locust; 
but  its  thorns  and  imperfect  shade  render  it  not  very  desirable. 

The  California  maple  {Acer  macrophyllum)  and  box  elder  (Negundo 
calif ornica)  have  done  fairly  well  in  the  lighter  alkali  lands  at  Tulare. 

A  most  remarkably  alkali-resistant  shrub  or  small  tree  is  the  pretty 
Koelreuteria  paniculata,  which  at  Tulare  is  growing  in  some  of  the 
strongest  alkali  soil  of  the  tract.  Unfortunately  it  is  available  mainly 
for  ornamental  purposes;  its  wood,  while  small,  is  very  hard  and  makes 
excellent  fuel. 

Irrigation  with  Saline  Waters. 

It  would  hardly  seem  necessary  to  emphasize  specially  the  danger 
incurred  in  irrigation  with  waters  containing  unusual  amounts  of  solu- 
ble salts;  since  ordinary  common  sense  clearly  indicates  the  impropriety 
of  increasing  the  saline  contents  of  soils  already  charged  with  them,  by 
the  evaporation,  year  after  year,  of  large  masses  of  saline  water.  Yet 
experience  has  shown  that  the  eagerness  to  utilize  for  irrigation  whatever 
water  happens  to  be  convenient  to  good  lands,  often  overcomes  both 
that  sense,  and  the  warning  given  by  the  published  analyses  of  such 
waters.  Without  specifiying  localities,  it  may  be  said  that  great  injury 
has  already  been  done  in  California  by  the  disregard  of  obviously 
needful  caution  in  this  respect.  The  very  slight  taste  possessed  by 
glauber  salt  and  salsoda  does  not  adequately  indicate  their  presence 
even  when  in  injurious  amounts;  so  that  frequently  a  chemical  test  of 
the  waters  is  the  only  definite  guide.  A  few  general  rules,  however, 
will  help  to  enable  the  irrigator  to  determine  whether  or  not  such 
examination  is  called  for. 

It  may  be  taken  for  granted  that  the  waters  of  all  lakes  having  no 
regular  outflow  are  unfit  for  regular  irrigation  use;  since  they  must  needs 
contain  all  the  accumulations  of  salts  from  the  secular  evaporation  of 
the  waters  that  flow  into  them. 


—  31  — 

The  plates  annexed  exhibit  the  cultural  results  of  several  years' 
irrigation  with  the  waters  of  Lake  Elsinore,  Riverside  County,  as  com- 
pared with  the  growth  of  orange  trees  on  the  same  land,  but  irrigated 
with  artesian  water.  Lake  Elsinore  is  fed  by  the  San  Jacinto  River, 
and  in  wet  years  sometimes  overflows  for  a  few  weeks  into  Temescal 
Creek.  Thus  its  saline  content  varies  somewhat,  from  about  80  to  over 
100  grains  per  gallon,  of  salts  containing  three-fifths  of  common  salt 
and  one-fifth  each  of  glauber  salt  and  carbonate  of  soda.  The  latter, 
as  already  stated,  tends  to  form  a  hardpan  in  the  subsoil,  and  such 
hardpan  was  actually  formed  where  the  water  was  used;  and  afterward 
prevented  its  proper  penetration,  so  that  the  trees  suffered  from  dryness 
of  their  lower  roots,  while  damaged  by  the  alkali  salts  near  the  surface. 
As  mentioned  before,  experience  elsewhere  has  shown  that  citrus  trees 
are  especially  sensitive  to  common  salt. 

The  investigations  made  by  the  Station  have,  moreover,  shown  that 
aside  from  the  frequently  saline  character  of  the  well  and  even  the 
artesian  waters  of  the  petroleum-bearing  region  of  the  State  in  the  coast 
ranges,  the  streams  of  that  region,  especially  the  smaller  ones,  are  some- 
times too  strongly  charged  with  "alkali"  (in  this  case  largely  the 
sulphates  of  soda  and  magnesia)  to  be  suitable  either  for  irrigation  or 
domestic  use.  Toward  the  end  of  the  dry  season,  even  the  larger  streams 
of  the  southern  coast  ranges,  with  their  diminished  flow,  sometimes  show 
an  excess  of  salts.  This  seems  also  to  be  true  of  the  San  Jacinto  River, 
which  feeds  Elsinore  Lake. 

The  waters  flowing  from  the  Sierra  Madre,  south  of  the  Tehachapi 
range,  are  throughout  of  excellent  quality  for  irrigation  purposes;  as 
are  all  those  flowing  from  the  Sierra  Nevada.  The  same  is  true  of  the 
artesian  waters  of  the  valley  of  Southern  California,  from  Los  Angeles 
east  to  Redlands,  and  of  all  the  deeper  borings  of  the  Antelope  Valley. 

In  the  Great  Valley,  the  artesian  waters  vary  greatly  in  quality. 
Those  of  Kern  and  Tulare  counties  are  mostly  good,  sometimes  excep- 
tionally so,  as  in  the  case  of  the  water-supply  of  Tulare  City.  It  is  only 
the  shallower  borings,  near  the  borders  of  Tulare  Lake,  that  some  waters 
strongly  charged  with  carbonate  of  soda  or  other  salts  have  been  found. 
From  Fresno  and  Merced  we  have  few  data  as  yet;  but  it  seems  that 
north  of  a  line  drawn  from  northeastern  Stanislaus  via  Tracy  to  Point 
of  Timber,  saline  waters,  sometimes  accompanied  by  some  gas,  occur  at 
certain  levels.  But  the  deep  wells  bored  at  Stockton  and  Sacramento, 
and  northward,  have  good  potable  water. 

Limits  of  Saline  Contents. — Unfortunately  it  is  not  easy  to  give  absolute 
rules  in  regard  to  the  exact  figures  that  constitute  an  excess  of  salts 
for  irrigation  purposes,  since  not  only  the  composition  of  the  salts, 
but  also  the  nature  of  the  land  to  be  irrigated,  and  the  frequency  of 
irrigation  required,  must  be  taken  into  consideration. 


3   ® 


5  ° 


#k 


3— B1 


(33) 


—  34  — 

Broadly  speaking,  the  extreme  limits  of  mineral  content  usually- 
assigned  for  potable  waters,  viz,  40  grains  per  gallon,  also  applies  to 
irrigation  waters.  Yet  it  sometimes  happens  that  all  or  most  of  the 
solid  content  is  gypsum  and  epsbm  salt;  when  only  a  large  excess  of 
the  latter  would  constitute  a  bar  to  irrigation  use.  When,  on  the  con- 
trary, a  large  proportion  of  the  solids  consists  of  carbonate  of  soda  or 
of  common  salt,  even  a  smaller  proportion  of  salts  than  40  grains 
might  preclude  its  regular  use,  depending  upon  the  nature  of  the  soil 
to  be  irrigated.  For  in  a  clay  loam,  or  a  heavy  adobe,  not  only  do  the 
salts  accumulate  nearer  to  the  surface,  but  the  subdrainage  being  slow 
and  imperfect  (unless  underdrained),  it  becomes  difficult  or  impossible 
to  wash  out  the  saline  accumulations  from  time  to  time,  as  is  feasible 
in  sandy  lands.  In  these,  moreover,  as  already  stated,  the  alkali  never 
becomes  as  concentrated  near  the  surface  as  in  heavier  soils.  Again, 
where  hardpan  exists  in  sandy  land,  saline  irrigation-water  soon 
saturates  the  soil  mass  above  it  with  salts. 

During  the  two  dry  seasons  just  past  saline  waters  have  frequently 
been  used,  exceptionally,  in  order  to  save  trees  threatened  with  death 
from  drought.  The  Station  has  even  advised  that  this  should  be  done, 
with  the  proviso  that  the  salts  so  introduced  must  be  washed  into  the  sub- 
drainage  by  heavy  irrigation,  whenever  practicable,  even  if  the  same 
saline  water  should  have  to  be  used  for  the  purpose.  For  few  such 
waters  are  sufficiently  strong  to  injure  vegetation  until  concentrated  by 
evaporation;  as  can  be  seen  from  the  vegetation  growing  close  to  the 
margins  of  alkaline  lakes,  with  its  roots  immersed  in  the  water. 

The  irrigator  can  determine  for  himself  whether  or  not  his  water  is 
of  doubtful  character,  by  evaporating  a  tablespoonful,  or  more,  in  a  clean 
silver  spoon  (avoiding  boiling).  If  the  dry  residue  should  form  simply 
a  thin,  powdery-looking  film  on  the  polished  metal,  he  may  be  assured 
that  the  water  is  all  right.  If,  on  the  other  hand,  an  obvious  saline 
crust  should  remain,  which  will  redissolve  in  water,  he  should  either 
have  an  analysis  made,  or  use  the  water  in  such  a  manner  as  to  remove 
the  accumulated  salts  from  time  to  time  by  washing  them  into  the 
subdrainage,  if  the  nature  of  the  soil  permits.  A  very  abundant  use  of 
such  ivaters  is  then  preferable  to  a  sparring  one;  but  the  user  should 
assure  himself  that  it  really  penetrates,  for  otherwise,  especially  in  case 
much  carbonate  of  soda  is  present,  a  dense  hardpan  may  be  formed  that 
will  allow  the  trees  to  perish  from  drought  despite  all  the  water  running 
in  the  irrigation  furrows.  A  pointed  steel  probe,  three-sixteenths  of  an 
inch  square,  provided  with  a  cross-handle,  like  a  hand  auger,  ought 
to  be  among  the  tools  of  every  farmer  for  such  tests  of  his  subsoil. 
No  farmer  in  the  arid  region  can  afford  to  be  ignorant  of  the  nature 
of  the  substrata  within  which  the  bulk  of  the  roots  of  his  crops  must 
vegetate. 


35 


Reclaimable  and  Irreclaimable  Alkali  Lands  as  Distinguished  by 
Their  Natural  Vegetation. 

While,  as  shown  above,  the  adaptation  or  non-adaptation  of  par- 
ticular alkali  lands  to  certain  cultures  may  be  determined  by  sampling 
the  soil  and  subjecting  the  leachings  to  chemical  analysis,  it  is  obvi- 
ously desirable  that  some  other  means,  if  possible  available  to  the 
farmer  himself,  should  be  found  to  determine  the  reclaimability  and 
adaptation  of  such  lands  for  general  or  special  cultures. 

The  natural  plant  growth  seems  to  afford  such  means,  both  as 
regards  the  quality  and  quantity  of  the  saline  ingredients.  The  most 
superficial  observation  shows  that  certain  plants  indicate  extremely 
strong  alkali  lands  where  they  occupy  the  ground  alone;  others  indi- 
cate preeminently  the  presence  of  common  salt;  the  presence  or  absence 
of  still  others  form  definite  or  probable  indications  of  reclaimability  or 
non-reclaimability.  Many  such  characteristic  plants  are  well  known 
to  and  readily  recognized  by  the  farmers  of  the  alkali  districts. 
"Alkali  weeds"  are  commonly  talked  about  almost  everywhere;  but  the 
meaning  of  this  term — i.  e.,  the  kind  of  plant  designated  thereby— 
varies  materially  from  place  to  place,  according  to  climate  as  well  as  to 
the  quality  of  the  soil.  Yet  if  these  characteristic  plants  could  be 
definitely  observed,  described,  and  named,  while  also  ascertaining  the 
amount  and  kind  of  alkali  they  indicate  as  existing  in  the  land,  lists 
could  be  formed  for  the  several  districts,  which  would  indicate,  in  a 
manner  intelligible  to  the  farmer  himself,  the  kind  and  degree  of 
impregnation  with  which  he  would  have  to  deal  in  the  reclamation 
work,  thus  enabling  him  to  go  to  work  on  the  basis  of  his  own  judg- 
ment, without  previous  reference  to  this  Station. 

The  carrying-out  of  such  a  plan  involves,  obviously,  a  very  large 
amount  of  botanical  as  well  as  chemical  work,  which  cannot  be  accom- 
plished within  a  few  seasons;  and,  in  view  of  the  wide  differences  in 
the  vegetation  of  the  several  alkali  regions  of  the  State,  the  same  work 
will  have  to  be  repeated  to  a  certain  extent  in  each  of  these  regions. 
The  object  to  be  achieved  is,  however,  of  such  high  practical  impor- 
tance— an  importance  not  remotely  appreciated  as  yet  by  those  not 
familiar  with  the  enormous  extent  of  otherwise  desirable  lands  in  this 
State  that  are  more  or  less  tainted  with  alkali — as  to  deserve  the 
expenditure  upon  it  of  a  large  amount  of  work  as  promptly  as  possible. 

The  extreme  limitation  of  funds  under  which  the  Agricultural  Col- 
lege, together  with  the  University  as  a  whole,  has  been  suffering  for 
some  years  past,  has  thus  far  restricted  the  scope  of  these  researches 
very  closely,  both  geographically  and  otherwise.  It  is  hoped  that  in 
the  future,  a  close  comparison  of  the  native  vegetation  with  the  chem- 
ical determination  of  the  quantity  and  kind  of  alkali  corresponding  to 


—  36  — 

certain  plants,  or  groups  of  plants,  naturally  occurring  on  the  land, 
may  enable  us  to  come  to  a  sufficiently  close  estimate  of  the  nature 
and  capabilities  of  the  latter  from  the  native  vegetation  alone,  or  with 
the  aid  of  test  plants  purposely  grown.  But  before  entering  upon  this 
complex  problem,  it  has  been  thought  best  to  determine,  first  of  all, 
what  lands  may  for  present  economic  conditions  be  considered  irre- 
claimable, because  their  improvement  would  involve  an  expense  out  of 
proportion  with  present  land  values.  So  far  as  large  areas  are  con- 
cerned, this  may  probably  be  considered  to  be  the  case  when  tile  under- 
drainage  is  required  in  order  to  wash  out  the  salts;  while  of  course 
smaller  tracts,  which  interrupt  the  cultivation  of  fields,  may  frequently 
justify  the  laying  of  a  few  drain  lines  required  to  render  them  cultiva- 
ble with  the  rest  of  the  land. 

As  stated  in  the  report  of  this  Station  for  1895-7,  the  field  work  of 
this  investigation,  both  botanical  and  in  the  collection  of  the  corre- 
sponding soil  samples,  has  been  done  by  Mr.  Joseph  Burtt  Davy, 
Assistant  Botanist  to  the  Station,  who  also  supplies  the  notes  accom- 
panying the  same;  while  the  laboratory  work  for  the  determination  of 
the  amounts  and  kinds  of  salts  present  in  the  several  cases  has  been 
carried  out  by  Prof.  R.  H.  Loughridge. 

The  plants  hereinafter  mentioned,  and  figured  for  the  benefit  of  the 
great  majority  of  readers  who  would  fail  to  recognize  them  from  the 
botanical  description  alone,  are  then  to  be  understood  as  indicating, 
whenever  they  occupy  the  ground  as  an  abundant  and  luxuriant  growth, 
that  such  land  is  irreclaimable  for  ordinary  crops,  unless  underdrained 
for  the  purpose  of  washing  out  surplus  salts.  The  occurrence  merely 
of  scattered,  more  or  less  stunted  individuals  of  these  plants,  while 
a  sure  indication  of  the  presence  of  alkali  salts,  does  not  necessarily 
show  that  the  land  is  irreclaimable. 

The  plants  which  may  best  serve  as  such  indicators  in  California  are 
the  following: 

Tussock-grass  (Sporobolus  airoides,  Torr.),  Fig.  9; 

Greasewood  (Sarcobatus  vermiculatus  (Hook.)  Torr.),  Fig.  10; 

Dwarf  Samphire  (Salicornia  subterminalis,  Parish,  and  other  species), 

Fig.  11; 

Bushy  Samphire  (Allenrolfea  occidentalis  (Wats.)  Ktze.),  Fig.  12; 
Saltwort   (Suaeda    Torreyana,    Wats.,  and  S.   suffrutescens,   Wats.), 
Fig.  13; 
Alkali-heath  (Frankcnia  grandifolia  campestris,  Gray),  Fig.  14; 
Cressa  (Cressa  c:etica  truxillensis,  Choisy),  Fig.  15. 


37  — 


TUSSOCK-GRASS*  (Sporobolus  airoides,  Torr.);  Fig.  9. 

The  three  sets  of  samples  of  Tussock-grass  soil  which  have  been  analyzed 
show  that  the  total  amount  of  all  salts  present  is  in  no  case  less  than 
49,000  pounds  per  acre,  to  a 
depth  of  four  feet,  and  that  it 
sometimes  reaches  the  extraor- 
dinarily high  figure  of  499,000 
pounds.  Of  these  amounts  the 
neutral  salts  (glauber  salt  and 
common  salt)  are  usually  in  the 
heaviest  proportion  (glauber  salt, 
19,600  to  323,000  pounds  per 
acre ;  common  salt,  3,500  to 
172,800);  the  corrosive  salsoda 
varying  from  3,000  to  44,000 
pounds.  —Tussock-grass  appar- 
ently cannot  persist  in  ground 
which  is  periodically  flooded.  It 
is  of  special  importance  because 
it  is  an  acceptable  forage  for 
stock. 

Tussock-grass  is  a  prevalent 
alkali-indicator  in  the  hot,  arid 
portions  of  the  interior,  from  the 
upper  San  Joaquin  Valley,  the 
Mojave  Desert,  and  southward; 
also  through  southern  Nevada 
and  Utah  as  far  east  as  Kansas 
and  Nebraska.  In  the  San  Joa- 
quin Valley  we  have  not  found  it    FlG  9    tussock-okas*-^^  abides,  Torr- 

farther    north    than    the    Tulare        (From  Division  of  Agrostology,  U.  S.  Dept.  Agr.) 

plains,  although  east  of  the  Sierra  it  occurs  near  Reno.  Coville  observes 
that  in  the  Death  Valley  region  "it  is  confined  principally  to  altitudes 
below  1,000  meters"  (3,280  feet).  Hillman,  however,  reports  it  from  near 
Reno,  Nevada,  at  an  altitude  which  cannot  be  much  less  than  4,500  feet. 
As  we  have  received  requests  for  precise  information  as  to  the  localities 
in  which  this  grass  grows,  from  persons  desiring  to  obtain  seed  for  trial, 
the  following  list  is  given:  Tulare  plains,  a  few  miles  southeast  of 
Tulare;  a  few  miles  south  of  Bakersfield;  in  the  Antelope  Valley;  along 
the  road  from  Rosamond  to  Lancaster,  and  in  alkali  sinks  about  the 
Leonis  Valley  between  Lancaster  and  Elizabeth  Lake.  It  is  reported 
by  Coville  from  Death  Valley,  Pahrump  Valley,  Resting-Springs  Valley? 

*  So-called  because  it  grows  in  large  clumps  or  tussocks,  which  feature  unfortunately 
is  not  indicated  in  the  illustration. 


38  — 


Owens  River  Valley,  and  other  points  in  the  desert  region  southeast  of 
the  Sierra  Nevada.  It  is  also  recorded  from  near  Barstow  and  other 
points  in  San  Bernardino  County;  in  dry  soils  near  Los  Angeles,  and 
from  San  Diego  County. 

GREASEWOOD*  (Sarcobatus  v ermicu I 'atus  (Hook)  Torr.);    Fig.  10. 

Through  the  courteous  cooperation  of  Prof.  F.  H.  Hillman,  Botanist  to 
the  Nevada  Agricultural  Experiment  Station  at  Reno,  we  have  obtained 
three  series  of  samples  of  Greasewood  soil  from  that  vicinity.    These  sam- 


Fig.  10.    Greasewood  (proper)— Sarcobatus  vermicutatus  (Hook)  Torr. 

A.  Appearance  of  a  branch  when  not  in  blossom. 

B.  Spiny  branchlet  from  the  same. 

C.  Branchlet  bearing  cones  of  male  flowers. 

D.  Cone  of  male  flowers  enlarged. 

E.  Branch  bearing  fruits. 

F.  Cluster  of  fruits  enlarged. 

G.  Vertical  section  through  a  fruit,  showing  the  seed  with  its 

curved  embryo,  (enlarged). 


*  This  is  the  true  Greasewood  of  the  desert  region  east  of  the  Sierra  Nevada,  and  not 
either  of  the  plants  known  under  that  name  in  the  San  Joaquin  Valley  and  in  Southern 
California. 


—  39  — 

pies  show  that  where  the  Greasewood  shrubs  are  thinly  scattered  and 
stunted  in  growth,  the  salt  content  per  acre  to  the  depth  of  three  feet 
is  about  2,400  pounds,  of  which  over  one  half  consists  of  the  corrosive 
carbonates.  Where  a  luxuriant  growth  occurs  the  total  salts  per  acre 
vary  from  38,000  to  58,500  pounds,  with  18,700  pounds  of  salsoda  and 
920  to  3,680  pounds  of  common  salt;  the  relative  percentage  of  the  inju- 
rious salsoda  is  thus  invariably  high.  The  common  salt  is  low  and  the 
neutral  glauber  salt  is  variable.  This  plant  therefore  always  indicates 
the  presence  of  "black  alkali." 

Greasewood  is  distinctly  a  plant  of  the  Great  Basin,  only  reaching 
California  in  the  adjacent  counties  of  Lassen.  Alpine,  Mono,  and 
northern  Inyo.  It  is  very  abundant  on  the  lower  levels  of  Honey  Lake 
Valley. 

DWARF  SAMPHIRE  (Salicornia  subterminalis,  Parish,  and  other  species  of 
the  interior) ;  Fig.  11. 


The  two  or  three  species  of  Dwarf  Samphire  which  grow  in  the  interior 
valleys   of  the  State   are   nowhere   very    abundant  in    those   portions 


Fig.  11.    Dwarf  Samphire— Salicornia  subterminalis,  Parish. 


—  40  — 

of  the  alkali  region  which  we  have  thus  far  investigated.  Wherever  the 
species  do  occur,  however,  they  are  confined  to  such  very  strongly  saline 
soils  that  they  may  be  considered  valuable  indicative  plants.  We  have 
as  yet  only  one  full  set  of  samples  of  Dwarf  Samphire  soil.  This  shows 
the  total  salt  content  to  amount  to  441,880  pounds  per  acre  in  a  depth  of 
four  feet.  The  neutral  glauber  salt  amounts  to  314,000  pounds,  almost 
as  much  as  in  Tussock-grass  soil ;  common  salt  up  to  1 25,640  pounds,  while 
the  salsoda  varies  from  2,200  to  12,000.  We  may  consider  this  plant  as 
indicative  of  almost  the  highest  percentage  of  common  salt,  glauber 
salt,  and  total  salts.  Like  the  preceding  species,  it  indicates  "white" 
salts  in  excessive  amounts,  and  a  subsoil  too  wet  for  the  Australian 
saltbush. 

Salicornia  subterminalis  occurs  in  San  Diego,  Riverside,  Los  Angeles, 
and  Kern  counties.  S.  herbacea  (L.)  is  reported  from  Riverside  County, 
and  from  the  margin  of  Tehachapi  Lake,  Kern  County.  S.  mucronata 
(Bigelow)  occurs  in  San  Diego  County;  and  a  fourth  species  is  found 
in  the  Antelope  Valley,  Los  Angeles  County;  near  Bakersfield,  Kern 
County;  and  at  Byron  Springs,  Contra  Costa  County.  These  inland 
species  all  differ  materially  in  habit  and  botanical  characters  from  the 
one  common  in  submerged  salt  marshes  along  the  seashore,  but  all  alike 
indicate  strongly  saline  soils. 

BUSHY  SAMPHIRE  (Allenrolfea  occidentalis  (Wats.)  Ktze.);   Fig.  12. 

This  plant  is  locally  called  greasewood,  but  as  this  name  is  much  more 
commonly  used  for  Sarcobatus  vermiculatus,  it  seems  best  to  call  Allen- 
rolfea  "bushy  samphire,"  as  it  closely  resembles  the  true  samphire  {Sali- 
cornia). 

Bushy  Samphire  usually  grows  in  low  sinks,  in  soil  which  in  winter 
is  excessively  wet  and  in  summer  becomes  a  "dry  bog."  Wherever  the 
plant  grows  luxuriantly  the  salt  content  is  invariably  high,  the  total 
salts  varying  from  327,000  pounds  per  acre,  to  a  depth  of  three  feet,  to 
494,520  pounds  in  four  feet.  The  salts  consist  mainly  of  glauber  and 
common  salts  (a  maximum  of  about  275,000  pounds  of  each);  salsoda 
varies  from  2,360  to  4,800  pounds  per  acre.  The  percentage  of  common 
salt  and  total  salts  is  higher  than  for  any  other  plant  investigated,  and  the 
glauber  salt  is  almost  proportionate.  The  areas  over  which  this  plant 
grows  must  therefore  be  considered  as  among  the  most  hopeless  of  alkali 
lands,  for  although  its  salts  are  "white,"  submergence  during  winter 
precludes  the  growth  of  Australian  saltbush. 

Bushy  Samphire  is  a  common  plant  in  alkali  soils  in  the  upper  San 
Joaquin  Valley,  around  Bakersfield  and  Delano;  a  few  stunted  bushes 
occur  near  the  margin  of  Tulare  Lake,  west  of  Tulare,  but  at  that  point 
it  appears  to  be  dying  out.  It  also  occurs  on  the  east  slope  of  Liver- 
more   Pass,  and  in   an  alkali  sink  in  a  pocket  of  the  hills  at  Byron 


Fig.  12.    Bushy  Samphire— AUenrolfea  occidentalis  (Wats.)  Ktze. 
[Called  "Greasewood"  in  San  Joaquin  Valley.] 


—  42  — 

Springs,  Contra  Costa  County.  In  the  Death  Valley  region  the  plant 
appears  to  be  very  abundant,  occupying  an  area  considerably  more 
southern  than  what  appears  to  be  the  southerly  limit  of  Greasewood 
(Sarcobatus). 

SALTWORT  (Suaeda  Torreyana,  Wats.,   S.  suffrutescens,  Wats.,  and   perhaps 
one  other  species);  Fig.  13. 

Samples  of  Saltwort  soil  from  Bakersfield,  Kern  County,  and  Byron 
Springs,  Contra  Costa  County,  taken  to  a  depth  of  one  foot  and  three 
feet  respectively,  show  that  this  plant  grows  luxuriantly  in  a  soil  con- 


Fig.  13.    Saltwort— Suaeda  Torreyana,  Wats. 


taining  130,000  pounds  of  salts  per  acre  in  the  first  foot,  and  with 
10,480  pounds  of  the  noxious  salsoda,  and  39,760  pounds  of  common 
salt  in  three  feet ;  while  only  a  sparse  growth  is  found  on  soils  contain- 
ing only  3,700  pounds  of  salts  in  three  feet.  It  thus  appears  to  indicate 
a  lower  percentage  of  salsoda  than  does  Greasewood,  but  a  higher  per- 
centage than  Bushy  Samphire.  Further  investigation  is  necessary 
to  determine  the  exact  relation  of  the  different  salts  to  the  growth 
of  the  plant,  and  as  to  whether  carbonates  always  occur  in  large  quantity; 
but  enough  data  have  been  gathered  to  show  that  a  luxuriant  growth 


43 


of  Saltwort  indicates  a  soil  practically  irreclaimable  except  at  the  ex- 
pense of  leaching. 

Suaeda  Torreyana  occurs  in  abundance  in  certain  alkali  soils  near 
Bakersfield,  Kern  County;  in  a  large  alkali  sink  near  Colusa  Junction, 
Colusa  County;  in  Honey  Lake  Valley,  Lassen  County;  Antelope  Valley, 
Kern  County;  and  in  the  vicinity  of  San  Bernardino.  Coville  reports 
having  collected  it  at  Lone  Pine,  Inyo  County.  The  closely  related 
species,  S.  suffrutescens,  only  to  be  distinguished  by  an  expert  botanist, 
occurs  in  abundance  in  the  alkali  soils  of  the  Mojave  Desert,  Death 
Valley,  the  Tulare  plains,  and  near  Bakersfield.  The  different  species 
of  Saltwort  grow  in  similar  habitats,  and  it  is  probable  that  the  condi- 
tion of  the  soil  is  approximately  the  same  for  each  species.  It  thus 
indicates  land  that  while  not  capable  of  bearing  ordinary  crops,  will 
probably  allow  the  Australian  saltbush  to  succeed,  at  least  with  the  aid 
of  some  gypsum. 

ALKALI-HEATH  (Frankenia  grandifolia  campestris,  Gray) ;  Fig.  14. 

Alkali-heath  is  perhaps  the  most  widely  distributed  of  any  of  our 
California  alkali  plants.  Its  perennial,  deep-rooting  habit  of  growth, 
and  flexible,  somewhat  wiry 
rootstock,  which  enables  it 
to  persist  even  in  cultivated 
ground,  render  it  a  valuable 
plant  as  an  alkali  indicator. 
The  salt  content  where  Al- 
kali-heath grows  luxuri- 
antly is  invariably  high, 
ranging  from  64,000  to 
282,000  pounds  per  acre; 
salsoda  varies  from  680  to 
19,590  pounds;  common 
salt  ranges  from  5,000  to 
10,000  pounds.  Such  soils 
would  not  be  benefited  by 
the  application  of  gypsum, 
as    the    salts    are    already 

largely  in  the  neutral  State.    FlG-  14-    Alkali- he \TH.—Frankenia  grandifolia  campeotris, 

Of  useful  plants  only  Salt- 
bushes  and  Tussock-grass  are  likely  to  flourish  in  such  lands. 

While  Alkali-heath  is  thus  one  of  the  most  alkali-tolerant  plants,  it 
is  at  the  same  time  capable  of  growth  with  a  minimum  of  salts  (total 
salts  3,700  pounds,  salsoda  680  pounds).  Where  only  a  sparse  growth 
of  this  plant  occurs,  therefore,  the  land  should  not  be  condemned  until 
a  chemical  examination  of  the  soil  has  been  made. 


44 


Alkali-heath  is  found  on  soils  of  very  varying  physical  texture  and 
degrees  of  moisture;  while  on  soils  of  uniform  texture  and  moisture,  but 
differing  in  chemical  composition,  it  varies  with  the  varying  salt- 
content. 

It  has  been  found  that  Australian  Saltbush  (Atriplex  semibaccata) 
can  be  successfully  grown  on  the  Colusa  County  "goose  lands,"  on  soil 
producing  a  medium  crop  of  Alkali-heath;  it  remains  to  be  shown 
whether  it  will  do  equally  well  on  soils  producing  a  dense  and  luxuriant 
growth  of  the  same. 

Alkali-heath  is  so  widely  distributed  throughout  the  interior  vallej^s 
of  California  that  it  would  be  superfluous  to  give  a  list  of  the  localities 
in  which  it  occurs.  A  closely  related  form  is  found  in  salt  marshes 
along  the  coast,  differing  from  that  of  the  interior  principally  in  its 
much  broader  leaves. 

CRESSA  (Cressa  cretica  truxillensis,  Choisy);  Fig.  15. 

Cressa  soils  show  a  low  percentage  of  the  noxious  salsoda,  but  com- 
paratively heavy  total  salts 
( 161,000  to  282,000  pounds  per 
acre.)  Common  salt  varies 
from  5,760  to  20,840  pounds 
per  acre  in  four  feet.  The 
maximum  is  lower  than  in 
the  case  of  Alkali-heath,  but 
Cressa  seems  to  be  much  more 
closely  restricted  to  strong 
alkali  than  does  the  former 
species.  Cressa  appears  to  be 
as  widely  distributed  through 
the  interior  valleys  of  the  State 
as  Alkali-heath.  It  is  a  cos- 
mopolitan plant,  occurring,  as 
its  name  indicates,  on  the  Ion- 
ian Isles,  as  well  as  in  North 
Africa,  Syria,  and  in  other 
arid  countries  of  the  world. 


Fl< 


15.    Cressa — Cressa  cretica  truxillensis,  Choisy. 


Relative  Tolerance  of  the  Different  Species. 

In  order  to  determine  the  relative  nature  of  the  soils  characterized 
by  each  of  the  above-named  plants,  Mr.  Davy  has  prepared  the  follow- 
ing table,  in  which  the  column  marked  optimum  shows,  as  nearly  as 
possible  with  our  present  knowledge  of  the  subject,  the  condition  of  the 
soil  where  each  species  grows  in  about  equal  luxuriance.  For  Saltwort 
and  Dwarf  Samphire  we  have  not  yet  been  able  to  obtain  as  thoroughly 
characteristic  soil  samples  as  could  be  desired,  but  we  hope  to  be  able  to 
do  so  during  the  coming  season. 


-  45  — 

It  must  be  understood  that  the  optimum  indicates  the  condition  under 
which  the  plant  has  been  found  at  its  greatest  luxuriance — where  it  is 
evidently  "at  home" — ;  whereas  the  maximum  and  minimum  have 
sometimes  been  obtained  where  the  plants  were  more  or  less  stunted  in 
growth  and  sparingly  scattered  over  the  ground. 


Table  Showing  Maximum,  Optimum,  and  Minimum  of  Salts  Tolekated  by  Each  of 
the  Several  Alkali  Plants. 


Pounds  Per  Acre. 


Optimum. 


Maximum. 


Minimum. 


Bushy  Samphire  . 
Dwarf  Samphires. 

Alkali-heath 


Total  Salts. 


Cressa 

Saltworts 

Greasewood  .. 
Tussock-grass 

Tussock-grass 
Alkali-heath.. 


Carbonates  (Salsoda). 


Greasewood  . 

Dwarf  Samphires. 

Saltworts 

Cressa 

Bushy  Samphire  . 


Chlorids  (Common  salt). 

Bushy  Samphire 

Dwarf  Samphires 

Saltworts 

Cressa. 


Alkali-heath 


Tussock-grass 
Greasewood  _. 


Sulphates  (Glauber  salt). 

Dwarf  Samphires. .j 

Bushy  Samphire 

Cressa 


Alkali-heath  . 

Saltworts 

Greasewood  . . 
Tussock-grass 


494,520 

441,880 

281,960) 

64,300  I" 

281,960 

130,000 

58,560 

49,000 

23,000 

*19,590) 

680 I 

18,720 

12,120 

10,480 

5,440 

4,800 

212,080 

125,640 

39,760 

20,840 

10,180) 

5,760f 

6,200 

3,680 


314,040 

277,640 

275,520 

275,520) 

34,530* 

44,160 

36,160 

19,640 


494,520 
441,880 

499,040 

281,960 

153,020 

58,560 

499,040 

44,460 

19,590 

18,720 

12,120 

12,120 

5,440 

4,800 

275,160 

125,640 

52,900 

20,840 

212,080 

172,800 
3,680 


314,040 
277,640 
275,520 

323,200 

104,040 

36,160 

323,200 


135,060 
441,880 

3,720 

161,160 

3,720 

2,400 

49,000 

3,040 

680 

1,280 
2,200 
1,120 
680 
1,500 

56,800 

125,640 

1,040 

5,760 

1,040 

3,530 
160 


314,040 

50,080 

134,880 

1,560 

1,560 

960 

19,640 


*  This  plant  grows  with  equal  luxuriance  in  soils  containing  only  G80  pounds  of  carbonates. 

In  these  tables  the  sequence  of  the  different  plants  has  been  arranged 
so  that  in  each  case  the  species  having  the  highest  optimum  comes  at 


—  46  — 

the  head  of  the  list.  Arranged  in  this  way  the  tables  show  that  where 
these  plants  grow  in  luxuriance  they  may  be  considered  indicative  of 
the  following  conditions  : 

Total  Salts  Indicators. — The  Samphires,  Alkali-heath,  and  Cressa  are 
all  indicative  of  excessive  total  salts.  Saltwort,  Greasewood,  and 
Tussock-grass  indicate  much  lower  total  salt-content;  indeed,  the 
maximum  of  the  two  latter  plants  ( Greasewood  and  Tussock-grass)  is 
so  low  that  the  application  of  gypsum  (land-plaster)  would  in  some 
cases  (e.  g.  the  Tussock-grass  lands  near  Bakersfield)  render  the  soil 
adapted  to  the  cultivation  of  Modiola  and  Australian  Saltbush. 

Salsoda  Indicators. — It  is  noticeable  that  the  relative  position  of  the 
different  species  in  the  columns  of  optimum  and  maximum  is  more 
uniform  in  the  salsoda  table  than  in  any  other;  and  whether  we 
arrange  the  sequence  of  the  plants  according  to  the  optimum  or  to 
the  maximum,  the  same  relative  position  is  maintained.  This  is  in 
complete  accord  with  what  our  knowledge  of  the  effect  of  salsoda  on 
vegetable  life  would  lead  us  to  expect;  being  by  far  the  most  injurious 
of  the  alkali  salts,  the  range  of  tolerance  is  much  smaller,  and  the  limits 
are  much  more  clearly  defined  than  in  the  case  of  the  other  salts. 

Luxuriant  growths  of  Tussock-grass  and  Greasewood  are  invariably 
indicative  of  high  percentages  of  carbonates,  but  in  such  cases  the  total 
salt  percentage  is  sometimes  so  low  that  the  application  of  gypsum  (land- 
plaster)  would  render  the  land  fit  for  the  cultivation  of  Modiola  or  even 
Australian  Saltbush,  as  noted  above.  It  must  be  borne  in  mind,  how- 
ever, that  where  Tussock-grass  grows  but  sparsely,  the  total  salt-content 
may  reach  499,000  pounds,  an  amount  rendering  the  land  utterly  worth- 
less for  agricultural  purposes  unless  the  surplus  salts  can  be  removed. 

Alkali-heath  cannot  be  taken  as  an  accurate  gauge  of  the  salsoda 
content,  as  it  grows  with  equal  luxuriance  on  soils  containing  respect- 
ively 680  and  19,590  pounds  to  the  acre,  of  this  salt. 

The  Samphires  and  Saltworts  are  relatively  low  down  in  the  carbonate 
table,  and  may  be  taken  to  indicate  a  comparatively  low  percentage  of 
"  black  alkali." 

Neutral-Salt  Indicators. — The  Samphires  and  Saltworts  head  the 
neutral-salt  tables,  and  are  reliable  indicators  of  excessively  high  per- 
centages both  of  glauber  salt  and  of  common  salt.  Saltwort  comes 
next  to  Samphire  in  the  common-salt  table,  but  is  not  quite  such  a 
good  guide  to  the  glauber  salt. 

Luxuriant  growths  of  Alkali-heath,  Greasewood,  and  Tussock-grass 
indicate  low  percentages  of  the  neutral  salts,  but  these  plants  will  some- 
times tolerate  (in  a  sparse  state  of  growth)  very  high  percentages. 

o 


